Fixes application crashes when calculating the winning page classification category - 1.5.x

[tmancey]

Uplift of #4770
Resolves brave/brave-browser#7866

Approved, please ensure that before merging:

• You have checked CI and the builds, lint, and tests all pass or are not related to your PR.
• You have tested your change on Nightly.
• The PR milestones match the branch they are landing to.

After you merge:

• The associated issue milestone is set to the smallest version that the changes is landed on.

[kjozwiak]

Restarting macOS as test-unit and test-browser failed as per the following:

• test-unit failure --> https://ci.brave.com/job/brave-browser-build-pr/job/issues%252F7866-1.5.x/1/execution/node/643/log/
• test-browser failure --> https://ci.brave.com/job/brave-browser-build-pr/job/issues%252F7866-1.5.x/1/execution/node/675/log/

[kjozwiak]

Uplift into 1.5.x approved after deliberating with @brave/uplift-approvers. Both CI/Jenkins and CI/Travis passed without any failures. QA also went through the PR on Nightly as per #4770 (comment).

Please make sure that all the correct labels are being used and the associated issue is moved into the correct milestone.