Disable testcontainers/ryuk in CI

testcontainers/ryuk is a resource reaper used for cleaning things up
after tests complete. In CI we only run tests once after which the
VM is shut down. Ryuk fetching happens while creating a `CatsResource`
that is counted towards timeout. This can take a long time in CI and
rarely happens at dev time.
Therefore, for CI ryuk is now disabled.

.github/workflows/ci.yml

@@ -19,16 +19,11 @@ jobs:
         with:
           java-version: 11
 
-      - name: Download test requirements
-        run: |
-          docker pull testcontainers/ryuk:0.5.1
-          docker pull localstack/localstack:2.3.2
-
       - name: Check Scala formatting
         run: sbt scalafmtSbtCheck scalafmtCheckAll
 
       - name: Run tests
-        run: sbt clean +test
+        run: env TESTCONTAINERS_RYUK_DISABLED=true sbt clean +test
 
       - name: Check binary compatibility
         run: sbt mimaReportBinaryIssues