Use go 1.21 for all workflow jbos

Author: cschleiden

.github/workflows/go.yml

@@ -51,7 +51,7 @@ jobs:
     - name: Set up Go
       uses: actions/setup-go@v3
       with:
-        go-version: 1.19
+        go-version: 1.21
         check-latest: true
         cache: true
 
@@ -85,7 +85,7 @@ jobs:
     - name: Set up Go
       uses: actions/setup-go@v3
       with:
-        go-version: 1.19
+        go-version: 1.21
         check-latest: true
         cache: true
 
@@ -111,7 +111,7 @@ jobs:
     - name: Set up Go
       uses: actions/setup-go@v3
       with:
-        go-version: 1.19
+        go-version: 1.21
         check-latest: true
         cache: true