test: print configurations built in CI run

In the check-build-coverage step at the end of the CI pipeline, also
collect all the build configurations that were built in the specific
pipeline (identified by the CI_COMMIT_SHA) in the build info and print
it in the log.

This makes it a tiny bit more convenient to check which images were
rebuilt and see if any images weren't rebuilt when they were meant to or
were rebuilt when they weren't expected to.

test/generators/check-build-coverage

@@ -13,7 +13,9 @@ SKIPS = [
 
 
 def check_build_coverage(cachedir):
+    ci_commit = os.environ.get("CI_COMMIT_SHA")
     tests = set()
+    built_now = set()
     for root, dirs, files in os.walk(cachedir):
         for fname in files:
             _, ext = os.path.splitext(fname)
@@ -27,6 +29,12 @@ def check_build_coverage(cachedir):
             image = build_info["image-type"]
             tests.add((distro, arch, image))
 
+            commit = build_info["commit"]
+            config = build_info["config"]
+            if commit == ci_commit:
+                # config was rebuilt in this run: collect and report
+                built_now.add((distro, arch, image, config))
+
     all_combos = set()
     for config in testlib.list_images(arches=["x86_64", "aarch64"]):
         distro = config["distro"]
@@ -37,7 +45,7 @@ def check_build_coverage(cachedir):
         all_combos.add((distro, arch, image))
 
     missing = all_combos - tests
-    return missing
+    return missing, built_now
 
 
 def main():
@@ -47,7 +55,16 @@ def main():
     cachedir = args.cachedir
     testlib.dl_s3_configs(cachedir)
 
-    missing = check_build_coverage(cachedir)
+    missing, now = check_build_coverage(cachedir)
+
+    if now:
+        print("Configurations built in this pipeline")
+        for build in now:
+            distro, arch, image, config = build
+            print(f"✅ {distro} {arch} {image} {config}")
+    else:
+        print("⭕ No images were built in this pipeline")
+
     if missing:
         print(f"❌ {len(missing)} distro/arch/image combinations have no builds in the cache")
         for idx, m in enumerate(missing, start=1):