ci: Make cirrus cache folders relative to cirrus base dir

.cirrus.yml

@@ -6,6 +6,7 @@ env:
   TEST_RUNNER_PORT_MIN: "14000"  # Must be larger than 12321, which is used for the http cache. See https://cirrus-ci.org/guide/writing-tasks/#http-cache
   CCACHE_SIZE: "200M"
   CCACHE_DIR: "/tmp/ccache_dir"
+  CCACHE_NOHASHDIR: "1"  # Debug info might contain a stale path if the build dir changes, but this is fine
 
 cirrus_ephemeral_worker_template_env: &CIRRUS_EPHEMERAL_WORKER_TEMPLATE_ENV
   DANGER_RUN_CI_ON_HOST: "1"  # Containers will be discarded after the run, so there is no risk that the ci scripts modify the system
@@ -39,9 +40,9 @@ global_task_template: &GLOBAL_TASK_TEMPLATE
   ccache_cache:
     folder: "/tmp/ccache_dir"
   depends_built_cache:
-    folder: "/tmp/cirrus-ci-build/depends/built"
+    folder: "depends/built"
   depends_sdk_cache:
-    folder: "/tmp/cirrus-ci-build/depends/sdk-sources"
+    folder: "depends/sdk-sources"
   ci_script:
     - ./ci/test_run_all.sh
 
@@ -114,7 +115,7 @@ task:
   << : *CREDITS_TEMPLATE
   << : *GLOBAL_TASK_TEMPLATE
   depends_releases_cache:
-    folder: "/tmp/cirrus-ci-build/releases"
+    folder: "releases"
   container:
     image: ubuntu:bionic
   env:
@@ -204,7 +205,7 @@ task:
 task:
   name: 'ARM64 Android APK [focal]'
   depends_sources_cache:
-    folder: "/tmp/cirrus-ci-build/depends/sources"
+    folder: "depends/sources"
   << : *GLOBAL_TASK_TEMPLATE
   container:
     image: ubuntu:focal