Update go semver to use ~ range.

Only pins to go minor, rather than patch.
Allows golang to be updated to latest patch, fixing CVEs blocking unit
tests.

Author: MirahImage

.github/workflows/pr.yml

@@ -5,7 +5,7 @@ on:
     branches: [ main ]
 
 env:
-  GO_VERSION: 1.19.2
+  GO_VERSION: ~1.19.3
   K8S_VERSION: v1.24.1
 
 jobs:

.github/workflows/prometheus-rules.yml

@@ -7,7 +7,7 @@ on:
     - observability/prometheus/rules/**/*.y*ml
 
 env:
-  GO_VERSION: 1.19.2
+  GO_VERSION: ~1.19.2
 
 jobs:
   rules: