[PHP] Update GuzzleHttp version to 7

[heissb2342]

Fix #7869,
Updated composer.mustache to contain guzzlehttp/guzzle ^7.3 and guzzlehttp/psr7 ^2.0 as methods of these libraries are directly used in api.mustache. As ConnectException is no longered extending RequestException, it is separately caught and converted into an ApiException. References to deprecated/removed function were replaced by their appropriate replacements.
Further switching to HTTPS was necessary in the .yaml file used in PHP test code generation, as all PetStore integration tests failed with 405 HTTP status code. Additionally a spin method was implemented to retry getting updated pet data for assertion.

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@jebentier, @dkarlovi, @mandrean, @jfastnacht, @ackintosh, @ybelenko, @renepardon

[wing328]

Can you please undo changes in this file?

We run a local instance of the petstore server, which doesn't have TLS setup: https://github.com/OpenAPITools/openapi-generator/wiki/Integration-Tests#how-to-add-integration-tests-for-new-petstore-samples

[heissb2342]

Ok, I tried running the PHP integrationtests locally, which all failed. So the tests are not run against the actual petstore, but a locally docker instance. Maybe I can even drop the first commit entirely.

[wing328]

I will try to test it locally with a petstore server. Let me know once you've finalized all the changes and I'll do the tests.

[heissb2342]

Hi @wing328, I reverted the change as you asked with the nice benefit of getting rid of most of the changed files as I hoped it would. Thanks for the pointer with running the petstore in a local container, the tests ran stable and without issues. If you like you can rerun them again, but as I was able to, this should not be necessary, especially if all the merge checks are green.

[wing328]

Tested locally and the result is good:

PHPUnit 9.5.8 by Sebastian Bergmann and contributors.

* Closing connection 0
* Closing connection 0
................................................................. 65 / 73 ( 89%)
........                                                          73 / 73 (100%)

Time: 00:01.297, Memory: 12.00 MB

OK (73 tests, 220 assertions)

[wing328]

@heissb2342 thanks a lot for the PR, which has been merged into master and will be included in the upcoming v5.3.0 release.