Guzzle related fixes

[GrahamCampbell]

Brief Summary of Changes

This fixes a few issues:

1. Bump minimum Guzzle versions to avoid known security vulnerabilities.
2. Add missing implicit dependencies on other Guzzle packages.
3. Upgrade Guzzle promises functions to avoid the old API that was deprecated in 1.4.0 (released 2020) and removed in 2.0.0.

What does this PR address?

• GitHub issue (Add reference - #XX)
• Refactoring
• New feature
• Bug fix
• Adds more tests

Are tests included?

• Yes
• No

Reviewer, please note:

Related to guzzle/guzzle#3144 and guzzle/guzzle#3145.

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I ran the full test suite before pushing the changes and all of the tests pass.

[const-cloudinary]

@GrahamCampbell thank you for contribution!