Point workflows at new python requirements file

[DellaBitta]

Description

Provide details of the change, and generalize the change in the PR title above.

Fixes to the Check Secure and Packaging workflows to point them to the. new python requirements file gha/scripts/requirements.txt.

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Testing

Describe how you've tested these changes. Link any manually triggered Integration tests or CPP binary SDK Packaging Github Action workflows, if applicable.

Packaging Worfklow

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Type of Change

Place an x the applicable box:

• Bug fix. Add the issue # below if applicable.
• New feature. A non-breaking change which adds functionality.
• Other, such as a build process or documentation change.

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Notes

• Bug fixes and feature changes require an update to the Release Notes section of release_build_files/readme.md.
• Read the contribution guidelines CONTRIBUTING.md.
• Changes to the public API require an internal API review. If you'd like to help us make Firebase APIs better, please propose your change in a feature request so that we can discuss it together.

[github-actions]

❌  Integration test FAILED

Requested by @DellaBitta on commit 4016745
Last updated: Tue Jul 19 11:19 PDT 2022
View integration test log & download artifacts

Failures	Configs
missing_log	[TEST] [ERROR] [Android] [1/3 os: windows] [1/2 android_device: emulator_target]
firestore	[TEST] [ERROR] [Android] [1/3 os: ubuntu] [1/2 android_device: android_target] [TEST] [FLAKINESS] [Android] [1/3 os: macos] [1/2 android_device: android_target] (1 failed tests)   ServerTimestampTest.TestServerTimestampsUsesPreviousValueFromLocalMutation [TEST] [FLAKINESS] [iOS] [macos] [1/2 ios_device: ios_target] (1 failed tests)   CRASH/TIMEOUT

Add flaky tests to go/fpl-cpp-flake-tracker

[AlmostMatt]

FYI - I think this will change back to "python_requirements" soon, it was a side effect of rolling back a change that will be roll-forwarded soon with a fix
https://github.com/firebase/firebase-cpp-sdk/pull/1033/files

[dconeybe]

@AlmostMatt I left a comment on the roll-forward PR, #1033, to make sure to roll forward this change too.