Fix logic 2

Author: flobernd

.github/workflows/check-backport-labels.yml

@@ -90,6 +90,9 @@ jobs:
             exit 1
           fi
 
+          // Validate that a floating backport label exists for each exact backport label major
+          // version.
+
           has_floating_backport_labels=true
 
           for pr_major in "${pr_majors[@]}"; do
@@ -121,3 +124,27 @@ jobs:
           if [ "${has_floating_backport_labels}" != true ]; then
             exit 1
           fi
+
+          // Validate that an exact backport label exists for each floating backport label major
+          // version.
+
+          has_exact_backports_labels=true
+
+          for pr_floating_major in "${pr_floating_majors[@]}"; do
+            exists_exact_major=false
+            for pr_major in "${pr_majors[@]}"; do
+              if [ "${pr_floating_major}" -eq "${pr_major}" ]; then
+                has_exact_major=true
+              fi
+            done
+
+            if [ "${has_exact_major}" != true ]; then
+              has_exact_backport_labels=false
+              echo "::error::Missing exact backport label for '${pr_floating_major}.x'"
+            fi
+          done
+
+          if [ "${has_exact_backport_labels}" != true ]; then
+            exit 1
+          fi
+