Fix build errors

[jayam04]

Overview

1. This PR fixes or fixes part of #[fill_in_number_here].
2. This PR does the following: [Explain here what your PR does and why]
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

Please follow the instructions for making a code change.

• 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

PR Pointers

• Never force push! If you do, your PR will be closed.
• To reply to reviewers, follow these instructions: https://github.com/oppia/oppia/wiki/Make-a-pull-request#step-5-address-review-comments-until-all-reviewers-approve
• Some e2e tests are flaky, and can fail for reasons unrelated to your PR. We are working on fixing this, but in the meantime, if you need to restart the tests, please check the "If your build fails" wiki page.
• See the Code Owner's wiki page for what code owners will expect.

[testbot-oppiabot]

Hi @jayam04, 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!

[testbot-oppiabot]

Hi @DubeySandeep, @oppia/web-tech-leads I cannot decide what to do with this PR, please assign reviewers manually thanks!

[testbot-oppiabot]

Hi @DubeySandeep, @oppia/web-tech-leads I cannot decide what to do with this PR, please assign reviewers manually thanks!

[testbot-oppiabot]

Hi @DubeySandeep, @oppia/web-tech-leads I cannot decide what to do with this PR, please assign reviewers manually thanks!

[testbot-oppiabot]

Hi @DubeySandeep, @oppia/web-tech-leads I cannot decide what to do with this PR, please assign reviewers manually thanks!

[testbot-oppiabot]

Hi @DubeySandeep, @oppia/web-tech-leads I cannot decide what to do with this PR, please assign reviewers manually thanks!