Bump guardian/setup-scala from 1 to 2

Bumps [guardian/setup-scala](https://github.com/guardian/setup-scala) from 1 to 2.
- [Release notes](https://github.com/guardian/setup-scala/releases)
- [Commits](guardian/setup-scala@v1...v2)

---
updated-dependencies:
- dependency-name: guardian/setup-scala
  dependency-version: '2'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yaml

@@ -13,7 +13,7 @@ jobs:
       - uses: actions/checkout@v7.0.1
 
       - name: Setup Java and sbt
-        uses: guardian/setup-scala@v1
+        uses: guardian/setup-scala@v2
 
       - name: SBT
         run: sbt clean compile test Universal/packageBin