Dynamically adapt between Spring versions

[mdeinum]

Dynamically adapt between Spring versions 6 (and potentially lower) and Spring Framework 7.

What does this PR do?

Add support for Spring Framework 7 for the ClientHttpRequestFactory support that is in there. Dynamically adapts to Spring Framework 7 or lower based on available methods.

Checklist

• This is an enhancement of existing features, or a new feature in existing plugins
  • I have updated CHANGELOG.next-release.md
  • I have added tests that prove my fix is effective or that my feature works
  • Added an API method or config option? Document in which version this will be introduced
  • I have made corresponding changes to the documentation
• This is a bugfix
  • I have updated CHANGELOG.next-release.md
  • I have added tests that would fail without this fix
• This is a new plugin
  • I have updated CHANGELOG.next-release.md
  • My code follows the style guidelines of this project
  • I have made corresponding changes to the documentation
  • I have added tests that prove my fix is effective or that my feature works
  • New and existing unit tests pass locally with my changes
  • I have updated supported-technologies.md
  • Added an API method or config option? Document in which version this will be introduced
  • Added an instrumentation plugin? Describe how you made sure that old, non-supported versions are not instrumented by accident.
• This is something else
  • I have updated CHANGELOG.next-release.md

[cla-checker-service]

❌ Author of the following commits did not sign a Contributor Agreement:
d98cfad, c270bc9

Please, read and sign the above mentioned agreement if you want to contribute to this project

[github-actions]

🤖 GitHub comments

Just comment with:

• run docs-build : Re-trigger the docs validation. (use unformatted text in the comment!)

[Mistborn94]

Support for Spring Boot 4 / Spring framework 7 also implemented in #4397 , but without the method handles.

[botelastic]

Hi! We just realized that we haven't looked into this issue in a while. We're sorry! We're labeling this issue as stalled to make it hit our filters and make sure we get back to it in as soon as possible. In the meantime, it'd be extremely helpful if you could take a look at it as well and confirm its relevance. A simple comment with a nice emoji will be enough :+1. Thank you for your contribution!