Fix #129 (from release-scripts repo): Handle FIREBASE_CONFIG_* constants to allow for one release candidate

[JayVivarekar]

Overview

1. This PR fixes or fixes part of #[fill_in_number_here].
2. This PR does the following: This draft PR is created to get help in debugging the frontend coverage issue caused by code added to remove firebase constants from the codebase.
3. (For bug-fixing PRs only) The original bug occurred because: [Explain what
   the cause of the bug was, and which PR introduced it]

Essential Checklist

• The PR title starts with "Fix #bugnum: " or "Fix part of #bugnum: ...", followed by a short, clear summary of the changes.
• I have followed the instructions for making a code change.
• I have assigned the correct reviewers to this PR (or will leave a comment with the phrase "@{{reviewer_username}} PTAL" if I don't have permissions to assign reviewers directly).
• The linter/Karma presubmit checks pass on my local machine, and my PR follows the coding style guide).
• "Allow edits from maintainers" is checked. (See here for instructions on how to enable it.)

Testing doc (for PRs with Beam jobs that modify production server data)

• A testing doc has been written: ... (ADD LINK) ...
• (To be confirmed by the server admin) All jobs in this PR have been verified on a live server, and the PR is safe to merge.

Proof that changes are correct

Proof of changes on desktop with slow/throttled network

Proof of changes on mobile phone

Proof of changes in Arabic language

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[oppiabot]

Hi @JayVivarekar, can you complete the following:

1. The karma and linter checklist has not been checked, please make sure to run the frontend tests and lint tests before pushing.
   Thanks!

[oppiabot]

Hi @vojtechjelinek, @DubeySandeep, @kevintab95, PTAL at this PR, it modifies files in jobs or platform folders.
Also @JayVivarekar, please make sure to fill in the server jobs form for the new job or feature to be tested on the backup server. This PR can be merged only after the test run is successful. Please refer to this guide for details.
Thanks!

[seanlip]

@JayVivarekar Do you have any updates on this PR, per our recent discussion? (Did you manage to sort out the mocking issue?) Thanks!

[oppiabot]

Hi @JayVivarekar, I'm going to mark this PR as stale because it hasn't had any updates for 7 days. If no further activity occurs within 4 days, it will be automatically closed so that others can take up the issue.
If you are still working on this PR, please make a follow-up commit within 4 days (and submit it for review, if applicable). Please also let us know if you are stuck so we can help you!

[oppiabot]

Hi @JayVivarekar, I'm going to mark this PR as stale because it hasn't had any updates for 7 days. If no further activity occurs within 4 days, it will be automatically closed so that others can take up the issue.
If you are still working on this PR, please make a follow-up commit within 4 days (and submit it for review, if applicable). Please also let us know if you are stuck so we can help you!

[oppiabot]

Hi @JayVivarekar, I'm going to mark this PR as stale because it hasn't had any updates for 7 days. If no further activity occurs within 4 days, it will be automatically closed so that others can take up the issue.
If you are still working on this PR, please make a follow-up commit within 4 days (and submit it for review, if applicable). Please also let us know if you are stuck so we can help you!

[oppiabot]

Hi @JayVivarekar, can you complete the following:

1. The karma and linter checklist has not been checked, please make sure to run the frontend tests and lint tests before pushing.
   Thanks!

[oppiabot]

Hi @JayVivarekar, I'm going to mark this PR as stale because it hasn't had any updates for 7 days. If no further activity occurs within 4 days, it will be automatically closed so that others can take up the issue.
If you are still working on this PR, please make a follow-up commit within 4 days (and submit it for review, if applicable). Please also let us know if you are stuck so we can help you!