opengl-registry: add v20240721

[valgur]

Summary

Changes to recipe: opengl-registry/20240721

Motivation

A simple update to the package for an upcoming Dawn PR.
I also switched from the cci.* version names to the GL_GLEXT_VERSION value set in headers: 20240721.

Details

---

• Read the contributing guidelines
• Checked that this PR is not a duplicate: list of PRs by recipe
• Tested locally with at least one configuration using a recent version of Conan

[conan-center-bot]

Conan v1 pipeline ✔️

All green in build 1 (b756aec85b7981c14934ea2b097028def041bd4e):

• opengl-registry/cci.20220929:
  All packages built successfully! (All logs)

• opengl-registry/20240721:
  All packages built successfully! (All logs)

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Conan v2 pipeline ✔️

Note: Conan v2 builds are now mandatory. Please read our discussion about it.

All green in build 1 (b756aec85b7981c14934ea2b097028def041bd4e):

• opengl-registry/cci.20220929:
  All packages built successfully! (All logs)

• opengl-registry/20240721:
  All packages built successfully! (All logs)

[AbrilRBS]

Thanks! I think this is a good change :)

[perseoGI]

LGTM, we like the new version format for this case