changelog batch (#11517)

.changelog/11132.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+api: Fixed a bug where API or CLI clients could become unresponsive when cron expressions contained zero-padded months
+```

.changelog/11323.txt

@@ -0,0 +1,3 @@
+```release-note:improvement
+api: return HTTP204 on CORS pre-flight checks and allow dot in CORS header keys.
+```

.changelog/11325.txt

@@ -0,0 +1,3 @@
+```release-note:improvement
+hcl: tolerate empty strings for zero integer values in quota and job specification.
+```

.changelog/11490.txt

@@ -0,0 +1,3 @@
+```release-note:improvement
+metrics: Added metric for `client.allocated.max_memory`
+```