gstreamer: Add version 1.20

[mjimenofluendo]

Specify library name and version: gstreamer/1.20.4

The current recipe only contains the old 1.19 version of GStreamer, IMHO an update to the 1.20 is needed

---

• I've read the guidelines for contributing.
• I've followed the PEP8 style guides for Python code in the recipes.
• I've used the latest Conan client version.
• I've tried at least one configuration locally with the conan-center hook activated.

[CLAassistant]

All committers have signed the CLA.

[ghost]

I detected other pull requests that are modifying gstreamer/all recipe:

• GStreamer: Added new versions and conan v2 support #14907
• gstreamer: Support Conan V2 #13400

This message is automatically generated by https://github.com/ericLemanissier/conan-center-conflicting-prs so don't hesitate to report issues/improvements there.

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[SpaceIm]

Why is it not auto merged by bot since it's a version bump?

[conan-center-bot]

Conan v1 pipeline ✔️

All green in build 39 (2bb0b516a27b7de3fa688dfaece487b80ee38826):

• gstreamer/1.20.6@:
  All packages built successfully! (All logs)

• gstreamer/1.22.3@:
  All packages built successfully! (All logs)

---

Conan v2 pipeline ✔️

Note: Conan v2 builds may be required once they are on the v2 ready list

All green in build 38 (2bb0b516a27b7de3fa688dfaece487b80ee38826):

• gstreamer/1.22.3@:
  All packages built successfully! (All logs)

• gstreamer/1.20.6@:
  All packages built successfully! (All logs)

[memsharded]

I am fine with changing the URL to the gstreamer. instead of gitlab, because the later is non-navigable, but the former is.

[SSE4]

GitLab/GitHub auto-generated archives cannot be trusted.

[memsharded]

Suggested change

	url: "https://gstreamer.freedesktop.org/src/gstreamer/gstreamer-1.22.3.tar.xz"
	url: "https://gitlab.freedesktop.org/gstreamer/gstreamer/-/archive/1.22.3/gstreamer-1.22.3.tar.gz"

@uilianries suggest that they have had issues with the downloads from gstreamer.freedesktop, and gitlab downloads have been more reliable

[SSE4]

GitLab isn't reliable, as well as GitHub. they auto-generate these archives with git archive command. and sometimes they can upgrade git version, or change git config, after that sha256 no longer matches previously generated archive. it's annoying, but it already happened in the past multiple times.
see Git archive checksums may change and Content of all release source code asset tarballs has changed.
we know these URLs were problematic in the past, therefore they can be no longer trusted.

[memsharded]

Suggested change

	url: "https://gstreamer.freedesktop.org/src/gstreamer/gstreamer-1.20.6.tar.xz"
	url: "https://gitlab.freedesktop.org/gstreamer/gstreamer/-/archive/1.20.6/gstreamer-1.20.6.tar.gz"

[SSE4]

GitLab/GitHub auto-generated archives cannot be trusted.