feat: require Go >= 1.21 (#424) [Backport release-1.x]

.github/workflows/ci.yml

@@ -12,7 +12,10 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        go-version: ["1.19", "1.20"]
+        go-version:
+          - "1.21"
+          - "1.22"
+
     steps:
     - name: Set up Go ${{ matrix.go-version }}
       uses: actions/setup-go@v4

go.mod

@@ -1,6 +1,10 @@
 module github.com/hetznercloud/hcloud-go
 
-go 1.19
+// This is being kept at a lower value on purpose as raising this would require
+// all dependends to update to the new version.
+// As long as we do not depend on any newer language feature this can be kept at the current value.
+// It should never be higher than the lowest currently supported version of Go.
+go 1.21
 
 require (
 	github.com/google/go-cmp v0.5.9
@@ -14,11 +18,13 @@ require (
 	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/kr/text v0.2.0 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/prometheus/client_model v0.3.0 // indirect
 	github.com/prometheus/common v0.42.0 // indirect
 	github.com/prometheus/procfs v0.10.1 // indirect
+	github.com/rogpeppe/go-internal v1.12.0 // indirect
 	golang.org/x/sys v0.10.0 // indirect
 	golang.org/x/text v0.11.0 // indirect
 	google.golang.org/protobuf v1.30.0 // indirect