heptapod-ci: use strict module policy

Without this, test can silently fallback to other compatible policy in some
cases.

Differential Revision: https://phab.mercurial-scm.org/D8229

contrib/heptapod-ci.yml

@@ -16,7 +16,7 b' variables:'
         - cd tests/
         - echo "python used, $PYTHON"
         - echo "$RUNTEST_ARGS"
-        - $PYTHON run-tests.py --color=always $RUNTEST_ARGS
+        - HGMODULEPOLICY="$TEST_HGMODULEPOLICY" "$PYTHON" run-tests.py --color=always $RUNTEST_ARGS
 
 checks-py2:
     <<: *runtests
@@ -43,29 +43,34 b' test-py2:'
     <<: *runtests
     variables:
         RUNTEST_ARGS: "--blacklist /tmp/check-tests.txt"
+        TEST_HGMODULEPOLICY: c
 
 test-py3:
     <<: *runtests
     variables:
         RUNTEST_ARGS: "--blacklist /tmp/check-tests.txt"
         PYTHON: python3
+        TEST_HGMODULEPOLICY: c
 
 test-py2-pure:
     <<: *runtests
     variables:
         RUNTEST_ARGS: "--pure --blacklist /tmp/check-tests.txt"
+        TEST_HGMODULEPOLICY: py
 
 test-py3-pure:
     <<: *runtests
     variables:
         RUNTEST_ARGS: "--pure --blacklist /tmp/check-tests.txt"
         PYTHON: python3
+        TEST_HGMODULEPOLICY: py
 
 test-py2-rust:
     <<: *runtests
     variables:
         HGWITHRUSTEXT: cpython
         RUNTEST_ARGS: "--blacklist /tmp/check-tests.txt"
+        TEST_HGMODULEPOLICY: rust+c
 
 test-py3-rust:
     <<: *runtests
@@ -73,3 +78,4 b' test-py3-rust:'
         HGWITHRUSTEXT: cpython
         RUNTEST_ARGS: "--blacklist /tmp/check-tests.txt"
         PYTHON: python3
+        TEST_HGMODULEPOLICY: rust+c