ci: quote pod-level resource variable values

Runner requires string type for KUBERNETES_POD_* vars.
Match exact format used in reference PR924.

Author: orioly13

.gitlab-ci.yml

@@ -175,20 +175,20 @@ default:
     GRADLE_WORKERS: 4
     GRADLE_MEMORY_MIN: 1G
     GRADLE_MEMORY_MAX: 5G
-    KUBERNETES_POD_CPU_REQUEST: 6
-    KUBERNETES_POD_CPU_LIMIT: 6
-    KUBERNETES_POD_MEMORY_REQUEST: 16Gi
-    KUBERNETES_POD_MEMORY_LIMIT: 16Gi
+    KUBERNETES_POD_CPU_REQUEST: "6"
+    KUBERNETES_POD_CPU_LIMIT: "6"
+    KUBERNETES_POD_MEMORY_REQUEST: "16Gi"
+    KUBERNETES_POD_MEMORY_LIMIT: "16Gi"
 
 .tier_l:
   variables: &tier_l_variables
     GRADLE_WORKERS: 6
     GRADLE_MEMORY_MIN: 1G
     GRADLE_MEMORY_MAX: 6G
-    KUBERNETES_POD_CPU_REQUEST: 10
-    KUBERNETES_POD_CPU_LIMIT: 10
-    KUBERNETES_POD_MEMORY_REQUEST: 20Gi
-    KUBERNETES_POD_MEMORY_LIMIT: 20Gi
+    KUBERNETES_POD_CPU_REQUEST: "10"
+    KUBERNETES_POD_CPU_LIMIT: "10"
+    KUBERNETES_POD_MEMORY_REQUEST: "20Gi"
+    KUBERNETES_POD_MEMORY_LIMIT: "20Gi"
 
 .gitlab_base_ref_params: &gitlab_base_ref_params
   - |