Playwright in CI is broken

[myieye]

The last deployment to staging uncovered a few problems in our Playwright CI configuration:

High Priority, because it's preventing us from evaluating/getting results from our Playwright tests.

From this job:

• [x] The steps "Password protect Playwright traces" and "Upload Playwright results" are both configured to run even though we don't want to run Playwright tests in that job
• [x] "Upload Playwright results" runs even if "Password protect Playwright traces" fails, which is a bit of a security concern (and was likely not introduced by our transition to Node)

From this job:

• [x] Playwright tests fail to run with the error: line 1: pnpm: command not found
• [x] "Integration tests (.NET)" did not run, because "Playwright setup" failed. The .NET tests should run regardless of whether Playwright has issues.

[hahn-kev]

I've opened a PR for this, I fixed the issues related to running on the self hosted runner and the dotnet tests should run even if the playwright tests fail. I didn't do the others, someone else is welcome to pickup my PR to fix the rest of the issues mentioned above.

[rmunn]

Discovered that if we want the .NET Send/Receive tests to run, we'll need to upgrade our self-hosted runner to run Ubuntu 22.04, not 20.04. Opened https://github.com/sillsdev/languageforge-lexbox/issues/714 to track that.