Remove all double line breaks in markdown #1

CONTRIBUTING.md

@@ -1,55 +1,44 @@
 # Collaborative Development
 
 ## Prerequisites
-
 - [Git](https://git-scm.com/)
 - [GitHub](https://github.com/)
 
 ## Types of interaction
 
 ### A. Use
-
 Since the open license allows free use, no notification is required. 
 However, for the authors it is valuable information who uses the software for what purpose. 
 Indicators are `Watch`, `Fork` and `Starred` of the repository. 
 If you are a user, please add your name and details in USERS.cff
 
 ### B. Comment
-
 You can give ideas, hints or report bugs in issues, in PR, at meetings or other channels. 
 This is no development but can be considered a notable contribution. 
 If you wish, add your name and details to `CITATION.cff`.
 
 ### C. Contribute and Review
-
 You add code and become an author of the repository. 
 You must follow the workflow!
 
 ### D. Mantain and Release
-
 You contribute and take care of the repository. 
 You review and answer questions. 
 You coordinate and carry out the release.
 
-
 ## Workflow
-
 The workflow for contributing to this project has been inspired by the workflow described by [Vincent Driessen](https://nvie.com/posts/a-successful-git-branching-model/).
 
-
 ### 1. Describe the issue on GitHub
-
 Create [an issue](https://help.github.com/en/articles/creating-an-issue)
 in the GitHub repository. 
 The `issue title` describes the problem you will address. 
 This is an important step as it forces one to think about the "issue".
 Make a checklist for all needed steps.
 
-
 ### 2. Solve the issue locally
 
 #### 2.0. Get the latest version of the `develop` branch
-
 Load the `develop branch`:
 ```bash
 git checkout develop
@@ -61,15 +50,13 @@ git pull
 ```
 
 #### 2.1. Create a new (local) branch
-
 ```bash
 git checkout -b feature-1314-my-feature
 ```
 
 Naming convention for branches: `type`-`issue-nr`-`short-description`
 
 ##### type
-
 * main / stable / (master) - includes the current stable version
 * develop - includes all current developments
 * feature - includes the feature that will be implemented
@@ -79,11 +66,9 @@ Naming convention for branches: `type`-`issue-nr`-`short-description`
 The majority of the development will be done in `feature` branches.
 
 ##### issue-nr
-
 The `issueNumber` should be taken from Step 1. Do not use the "#". 
 
 ##### short-description
-
 Describe shortly what the branch is about. 
 Avoid long and short descriptive names for branches, 2-4 words are optimal.
 
@@ -96,7 +81,6 @@ Other hints:
 Examples of branch names: `feature-42-add-new-ontology-class` or `feature-911-branch-naming-convention`
 
 #### 2.2. Start editing the files
-
 - Divide your feature into small logical units
 - Start to write the documentation or a docstring
 - Don't rush, have the commit messages in mind
@@ -106,7 +90,6 @@ On first commit to the repo:
 - Add your name and details to CITATION.cff
 
 #### 2.3. Commit your changes 
-
 ```bash
 git commit filename.md
 ``` 
@@ -123,7 +106,6 @@ Write a good `commit message`:
 Examples of commit message: `Added function with some method #42` or `Update documentation for commit messages #1`
 
 #### 2.4 Fix your latest commit message
-
 You want to improve your latest commit message? 
 Your latest commit is not pushed yet? 
 Edit the commit message of your latest commit:
@@ -132,9 +114,7 @@ Edit the commit message of your latest commit:
 git commit --amend
 ```
 
-
 ### 3. Push your `local` branch on the remote server `origin`
-
 If your branch does not exist on the remote server yet, use:
 
 ```bash
@@ -147,9 +127,7 @@ Then push regularly with:
 git push
 ```
 
-
 ### 4. Submit a pull request (PR)
-
 Follow the GitHub guide [creating-a-pull-request](https://help.github.com/en/articles/creating-a-pull-request).
 The PR should be directed: `base: develop` <- `compare: feature-1-collaboration`.
 
@@ -159,20 +137,16 @@ When it is merged, it [automatically closes](https://help.github.com/en/github/m
 Assign a reviewer and get in contact.
 
 #### 4.0. Review the PR
-
 Follow the GitHub guide [approving a pull request with required reviews](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/approving-a-pull-request-with-required-reviews).
 Leave a small comment and some nice words of thanks.
 
 #### 4.1. Merge the PR
-
 Follow the GitHub guide [merging a pull request](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/incorporating-changes-from-a-pull-request/merging-a-pull-request).
 
 #### 4.2. Delete the feature branch
-
 Follow the GitHub guide [deleting a branch](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-and-deleting-branches-within-your-repository#deleting-a-branch).
 
 ### 5. Close the issue
-
 Document the result in a few sentences and close the issue.
 Check that all steps have been documented: