Move frontend build to GitHub Actions

[ioannakok]

There seems to be an issue with TeamCity on frontend. Sometimes it is not able to fetch from GitHub and has big delays in picking up pushes.

Example of recent failure:

Failed to collect changes, error: Error collecting changes for VCS repository '"DotcomFrontend2" {instance id=2109, parent internal id=263, parent id=dotcom_DotcomFrontend2, description: "[email protected]:guardian/frontend.git#refs/heads/main"}'
'git fetch' command failed (repository dir: <TeamCity data dir>/system/caches/git/git-6DD10713.git).
stderr: Picked up JAVA_TOOL_OPTIONS: -javaagent:/usr/local/log4j-hotpatch/Log4jHotPatch.jar=log4jFixerVerbose=false
Short read of block.
elapsed time: 13m:30s,641ms
exit code: 1, VCS root: "DotcomFrontend2" {instance id=2109, parent internal id=263, parent id=dotcom_DotcomFrontend2, description: "[email protected]:guardian/frontend.git#refs/heads/main"}

https://teamcity.gutools.co.uk/viewLog.html?buildId=850820&buildTypeId=dotcom_master

TeamCity resumed after this but the delays seem to be happening on a regular basis and we've had reports from other teams as well.

[georgeblahblah]

Moving to blocked until guardian/actions-riff-raff#33 is resolved