[9.18] chg: ci: Use make clean to reduce artifacts in successful jobs

Reduce the amount of artifacts stored by running make clean at the end
of unit and system test run. If any of the previous commands fail, the
runner will stop executing the commands in `script` immediately, so the
cleanup only happens if none of the previous commands failed.

The build artifacts from unit and system tests are re-used anywhere and
should be safe to throw away immediately.

Backport of MR !10015

Merge branch 'backport-nicki/reduce-ci-artifacts-9.18' into 'bind-9.18'

See merge request isc-projects/bind9!10019

.gitlab-ci.yml

@@ -53,6 +53,9 @@ variables:
 
   HYPOTHESIS_PROFILE: "ci"
 
+  # Some jobs may clean up the build artifacts unless this is set to 0.
+  CLEAN_BUILD_ARTIFACTS_ON_SUCCESS: 1
+
 default:
   # Allow all running CI jobs to be automatically canceled when a new
   # version of a branch is pushed.
@@ -364,6 +367,7 @@ stages:
     - >
       "$PYTEST" --junit-xml="$CI_PROJECT_DIR"/junit.xml -n "$TEST_PARALLEL_JOBS" | tee pytest.out.txt
     - '( ! grep -F "grep: warning:" pytest.out.txt )'
+    - test "$CLEAN_BUILD_ARTIFACTS_ON_SUCCESS" -eq 0 || ( cd ../../.. && make clean >/dev/null 2>&1 )
   after_script:
     - test -n "${OUT_OF_TREE_WORKSPACE}" && cd "${OUT_OF_TREE_WORKSPACE}"
     - *display_pytest_failures
@@ -433,6 +437,7 @@ stages:
     - test -n "${OUT_OF_TREE_WORKSPACE}" && cd "${OUT_OF_TREE_WORKSPACE}"
   script:
     - make -j${TEST_PARALLEL_JOBS:-1} -k unit V=1
+    - test "$CLEAN_BUILD_ARTIFACTS_ON_SUCCESS" -eq 0 || make clean >/dev/null 2>&1
   after_script:
     - test -d bind-* && cd bind-*
     - REALSOURCEDIR="$PWD"
@@ -886,7 +891,8 @@ system:gcc:bookworm:amd64:
   <<: *system_test_gcov_job
   variables:
     CI_ENABLE_ALL_TESTS: 1
-  needs:
+    CLEAN_BUILD_ARTIFACTS_ON_SUCCESS: 0
+  needs:  # using artifacts from unit test job is required for gcov
     - job: unit:gcc:bookworm:amd64
       artifacts: true
 
@@ -895,6 +901,7 @@ unit:gcc:bookworm:amd64:
   <<: *unit_test_gcov_job
   variables:
     CI_ENABLE_ALL_TESTS: 1
+    CLEAN_BUILD_ARTIFACTS_ON_SUCCESS: 0
   needs:
     - job: gcc:bookworm:amd64
       artifacts: true
@@ -1530,6 +1537,7 @@ respdiff:
     MAX_DISAGREEMENTS_PERCENTAGE: "0.15"
   script:
     - bash respdiff.sh -s named -q "${PWD}/100k_mixed.txt" -c 3 -w "${PWD}/rspworkdir" "${CI_PROJECT_DIR}" "/usr/local/respdiff-reference-bind/sbin/named"
+    - cd ../.. && make clean >/dev/null 2>&1
 
 respdiff:asan:
   <<: *respdiff_job
@@ -1543,6 +1551,7 @@ respdiff:asan:
     MAX_DISAGREEMENTS_PERCENTAGE: "0.15"
   script:
     - bash respdiff.sh -s named -q "${PWD}/100k_mixed.txt" -c 3 -w "${PWD}/rspworkdir" "${CI_PROJECT_DIR}" "/usr/local/respdiff-reference-bind/sbin/named"
+    - cd ../.. && make clean >/dev/null 2>&1
 
 respdiff:tsan:
   <<: *respdiff_job
@@ -1559,6 +1568,7 @@ respdiff:tsan:
     TSAN_OPTIONS: "${TSAN_OPTIONS_DEBIAN}"
   script:
     - bash respdiff.sh -s named -q "${PWD}/100k_mixed.txt" -c 3 -w "${PWD}/rspworkdir" "${CI_PROJECT_DIR}" "/usr/local/respdiff-reference-bind/sbin/named"
+    - cd ../.. && make clean >/dev/null 2>&1
   after_script:
     - *find_python
     - *parse_tsan
@@ -1573,6 +1583,7 @@ respdiff-third-party:
     MAX_DISAGREEMENTS_PERCENTAGE: "0.2"
   script:
     - bash respdiff.sh -s third_party -q "${PWD}/100k_mixed.txt" -c 1 -w "${PWD}/rspworkdir" "${CI_PROJECT_DIR}"
+    - cd ../.. && make clean >/dev/null 2>&1
 
 # Performance tests