Run CI in Github Actions (#22054)

* Tidy workflows

* Update get-version-from-git.sh

* Run tests in Actions

* Upload coverage to SonarCloud

* Run linters in Actions

* Run builds in Actions, consolidating with sentry uploader

* Update sonar-project.properties

* chmod +x

* Iterate

* Use new env vars

* Delete yarn-sub.js

* Use re-usable sonarqube action

* Add README badges

* Match reality

package.json

@@ -49,7 +49,8 @@
     "lint:js-fix": "eslint --fix src",
     "lint:types": "tsc --noEmit --jsx react",
     "lint:style": "stylelint \"res/css/**/*.scss\"",
-    "test": "jest"
+    "test": "jest",
+    "coverage": "yarn test --coverage"
   },
   "dependencies": {
     "@matrix-org/olm": "https://gitlab.matrix.org/api/v4/projects/27/packages/npm/@matrix-org/olm/-/@matrix-org/olm-3.2.8.tgz",