fix(ci): make composer check:strict able to fail on tests (#16)

test:unit and test:all ended in
  ./vendor/bin/phpunit --colors=always || echo 'No PHP test suite in this repo ... skipping...'
so phpunit's exit status was discarded unconditionally. The message was
true today (this repo is a Python ExApp wrapper with no PHP test suite)
but the mechanism was not conditional on it: any real test failure, now
or after a test suite is added, would have been swallowed the same way.

Replaced with a guard on the actual precondition, so an absent suite is a
visible stated fact and a present-but-failing suite fails the gate:
  if [ -f phpunit.xml ] || [ -f phpunit.xml.dist ]; then ./vendor/bin/phpunit --colors=always; else echo 'SKIPPED: no phpunit.xml ...'; fi

Positive control, measured on this tree in a PHP 8.3.32 container with a
freshly installed vendor/, injecting a phpunit.xml plus one deliberately
failing test:
  old composer.json + failing test -> check:strict exit 0  (swallowed)
  new composer.json + failing test -> check:strict exit 1, naming test:all
  new composer.json, test removed  -> check:strict exit 0, loud SKIPPED

Tooling only.

Author: rubenvdlinde

composer.json

@@ -25,8 +25,8 @@
 		"phpmetrics:violations": "./vendor/bin/phpmetrics --violations-xml=phpmetrics/violations.xml phpcs-custom-sniffs",
 		"psalm": "./vendor/bin/psalm --threads=1 --no-cache",
 		"phpstan": "./vendor/bin/phpstan analyse --memory-limit=1G",
-		"test:unit": "./vendor/bin/phpunit --colors=always || echo 'No PHP test suite in this repo (no phpunit.xml, no tests/) - skipping...'",
-		"test:all": "./vendor/bin/phpunit --colors=always || echo 'No PHP test suite in this repo (no phpunit.xml, no tests/) - skipping...'",
+		"test:unit": "if [ -f phpunit.xml ] || [ -f phpunit.xml.dist ]; then ./vendor/bin/phpunit --colors=always; else echo 'SKIPPED: no phpunit.xml in this repo - there is no PHP test suite to run'; fi",
+		"test:all": "if [ -f phpunit.xml ] || [ -f phpunit.xml.dist ]; then ./vendor/bin/phpunit --colors=always; else echo 'SKIPPED: no phpunit.xml in this repo - there is no PHP test suite to run'; fi",
 		"check": "E=0; for CMD in lint phpcs psalm test:unit; do echo; echo \"=== $CMD ===\"; composer $CMD || E=1; done; echo; if [ $E -eq 0 ]; then echo \"ALL CHECKS PASSED\"; else echo \"SOME CHECKS FAILED (see above)\"; fi; exit $E",
 		"check:full": "E=0; for CMD in lint phpcs psalm phpstan test:all; do echo; echo \"=== $CMD ===\"; composer $CMD || E=1; done; echo; if [ $E -eq 0 ]; then echo \"ALL CHECKS PASSED\"; else echo \"SOME CHECKS FAILED (see above)\"; fi; exit $E",
 		"check:strict": "E=0; for CMD in lint phpcs phpmd psalm phpstan test:all; do echo; echo \"=== $CMD ===\"; composer $CMD || E=1; done; echo; if [ $E -eq 0 ]; then echo \"ALL CHECKS PASSED\"; else echo \"SOME CHECKS FAILED (see above)\"; fi; exit $E",