Fix development environment documentation (#6099)

<!-- Raise an issue to propose your change
(https://github.com/opencv/cvat/issues).
It helps to avoid duplication of efforts from multiple independent
contributors.
Discuss your ideas with maintainers to be sure that changes will be
approved and merged.
Read the [Contribution
guide](https://opencv.github.io/cvat/docs/contributing/). -->

<!-- Provide a general summary of your changes in the Title above -->

### Motivation and context
<!-- Why is this change required? What problem does it solve? If it
fixes an open
issue, please link to the issue here. Describe your changes in detail,
add
screenshots. -->
Updated development environment documentation (fixed links, moved some
steps)
### How has this been tested?
<!-- Please describe in detail how you tested your changes.
Include details of your testing environment, and the tests you ran to
see how your change affects other areas of the code, etc. -->

### Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply.
If an item isn't applicable for some reason, then ~~explicitly
strikethrough~~ the whole
line. If you don't do that, GitHub will show incorrect progress for the
pull request.
If you're unsure about any of these, don't hesitate to ask. We're here
to help! -->
- [x] I submit my changes into the `develop` branch
- [ ] I have added a description of my changes into the
[CHANGELOG](https://github.com/opencv/cvat/blob/develop/CHANGELOG.md)
file
- [x] I have updated the documentation accordingly
- [ ] I have added tests to cover my changes
- [ ] I have linked related issues (see [GitHub docs](

https://help.github.com/en/github/managing-your-work-on-github/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword))
- [ ] I have increased versions of npm packages if it is necessary

([cvat-canvas](https://github.com/opencv/cvat/tree/develop/cvat-canvas#versioning),

[cvat-core](https://github.com/opencv/cvat/tree/develop/cvat-core#versioning),

[cvat-data](https://github.com/opencv/cvat/tree/develop/cvat-data#versioning)
and

[cvat-ui](https://github.com/opencv/cvat/tree/develop/cvat-ui#versioning))

### License

- [ ] I submit _my code changes_ under the same [MIT License](
https://github.com/opencv/cvat/blob/develop/LICENSE) that covers the
project.
  Feel free to contact the maintainers if that's a concern.

site/content/en/docs/contributing/development-environment.md

@@ -82,8 +82,6 @@ description: 'Installing a development environment for different operating syste
   pip install \
       -r cvat/requirements/development.txt \
       -r cvat/requirements/production.txt
-  python manage.py migrate
-  python manage.py collectstatic
   ```
 
   Note that the `.txt` files in the `cvat/requirements` directory
@@ -148,26 +146,6 @@ description: 'Installing a development environment for different operating syste
   >
   > Perform this action before installing cvat requirements from the list mentioned above.
 
-- Create a super user for CVAT:
-
-  ```bash
-  python manage.py createsuperuser
-  ```
-
-- Install npm packages for UI (run the following command from CVAT root directory):
-
-  ```bash
-  yarn --frozen-lockfile
-  ```
-
-  > Note for Mac users
-  >
-  > If you faced with error
-  >
-  > `Node Sass does not yet support your current environment: OS X 64-bit with Unsupported runtime (57)`
-  >
-  > Read this article [Node Sass does not yet support your current environment](https://marketplace.visualstudio.com/items?itemName=msjsdiag.debugger-for-chrome)
-
 - Install [Docker Engine](https://docs.docker.com/engine/install/ubuntu/) and [Docker-Compose](https://docs.docker.com/compose/install/)
 
 - Pull and run Open Policy Agent docker image:
@@ -188,6 +166,28 @@ description: 'Installing a development environment for different operating syste
   Note: use `docker start/stop cvat_db_debug` commands to start and stop the container.
   If it is removed, data will be removed together with the container.
 
+- Apply migrations and create a super user for CVAT:
+
+  ```bash
+  python manage.py migrate
+  python manage.py collectstatic
+  python manage.py createsuperuser
+  ```
+
+- Install npm packages for UI (run the following command from CVAT root directory):
+
+  ```bash
+  yarn --frozen-lockfile
+  ```
+
+  > Note for Mac users
+  >
+  > If you faced with error
+  >
+  > `Node Sass does not yet support your current environment: OS X 64-bit with Unsupported runtime (57)`
+  >
+  > Read this article [Node Sass does not yet support your current environment](https://marketplace.visualstudio.com/items?itemName=msjsdiag.debugger-for-chrome)
+
 ### Run CVAT
 - Start npm UI debug server (run the following command from CVAT root directory):
   - If you want to run CVAT in localhost:
@@ -214,7 +214,7 @@ description: 'Installing a development environment for different operating syste
 
 
 You have done! Now it is possible to insert breakpoints and debug server and client of the tool.
-Instructions for running tests locally are available [here](/site/content/en/docs/contributing/running-tests.md).
+Instructions for running tests locally are available [here](/docs/contributing/running-tests/).
 
 ## Note for Windows users
 

site/content/en/docs/contributing/running-tests.md

@@ -40,7 +40,7 @@ yarn run cypress:run:chrome:canvas3d
 
 **Initial steps**
 
-1. Follow [this guide](/site/content/en/docs/api_sdk/sdk/developer-guide/) to prepare
+1. Follow [this guide](/docs/api_sdk/sdk/developer-guide/) to prepare
    `cvat-sdk` and `cvat-cli` source code
 1. Install all necessary requirements before running REST API tests:
    ```

tests/python/README.md

@@ -20,7 +20,7 @@ the server calling REST API directly (as it done by users).
 ## How to run?
 **Initial steps**
 
-1. Follow [this guide](/site/content/en/docs/api_sdk/sdk/developer-guide/) to prepare
+1. Follow [this guide](../../site/content/en/docs/api_sdk/sdk/developer-guide.md) to prepare
    `cvat-sdk` and `cvat-cli` source code
 1. Install all necessary requirements before running REST API tests:
    ```