Update versions to 3.3.8

[lkbhitesh07]

Overview

1. This PR fixes or fixes part of N/A.
2. This PR does the following: Updates the version to latest.
3. (For bug-fixing PRs only) The original bug occurred because: N/A

Essential Checklist

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• [ ] I have linked the issue that this PR fixes in the "Development" section of the sidebar.
• [ ] I have checked the "Files Changed" tab and confirmed that the changes are what I want to make.
• [ ] I have written tests for my code.
• [ ] The PR title starts with "Fix #bugnum: " or "Fix part of #bugnum: ...", followed by a short, clear summary of the changes.
• [ ] I have assigned the correct reviewers to this PR (or will leave a comment with the phrase "@{{reviewer_username}} PTAL" if I can't assign them directly).

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[bot]]

Assigning @DubeySandeep for the first pass review of this PR. Thanks!