SFD-135 Set up workflow to run when merging PR's

[jmain-scottlogic]

SFD-135

• Change pull-request workflow to build and test.
• Update so runs when PR's merged into main
• Removed playwright workflow as covered by build and test
• Update test step in pages to run build and test workflow

[mgriffin-scottlogic]

We'll also need to change publish-package.yml as this calls the old pull-request.yml workflow as well. Not sure exactly what happens when a workflow is called twice as this calls the page publish too, will have to see if it does something sensible or builds and tests things twice.

[jmain-scottlogic]

Updated publish to point at build-and-test. Quickly looking into making the build-and-test step optional, but hit problem as github workflows don't seem to support conditional needs

[mgriffin-scottlogic]

Looks good, yeah Github Actions never seems to make it easy. There's some things you can do with conditionals but a lot of stuff is very easy to break and not know about it until things just don't run.