[0.73.x] Make NTP widget size to fit content

[cezaraugusto]

fix brave/brave-browser#6746 for 0.73.x

Sibling PRs #3916, #3938

[kjozwiak]

Restarting iOS due to https://ci.brave.com/job/brave-browser-build-pr/job/ca-6746-73/1/execution/node/466/log/ failing.

Restarting macOS due to https://ci.brave.com/job/brave-browser-build-pr/job/ca-6746-73/1/execution/node/505/log/ failing.

Restarting Win x64 due to the following failure as per https://ci.brave.com/job/brave-browser-build-pr/job/ca-6746-73/1/execution/node/158/log/:

14:27:35  HEAD is now at 0e9afd2a Change "CPU time" to "elapsed time"
14:27:35  Done updating submodules...
14:27:35  Syncing Gclient (with reset)
14:27:35  C:\6-73: gclient sync --force --nohooks --with_branch_heads --with_tags --upstream
14:27:35  Downloading CIPD client for windows-amd64 from https://chrome-infra-packages.appspot.com/client?platform=windows-amd64&version=git_revision:2a121dde003a3079db0fdf58195b52cbf486f6ba...
14:27:47  Cannot contact i-07088c87be60a8f93: hudson.remoting.ChannelClosedException: Channel "hudson.remoting.Channel@6e521720:i-07088c87be60a8f93": Remote call on i-07088c87be60a8f93 failed. The channel is closing down or has closed down

[kjozwiak]

Uplift into 0.73.x approved after deliberating with @brave/uplift-approvers. Both CI/Jenkins and CI/Travis passed without any issues.

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