Use the Go toolchain installed by actions/setup-go

Since version 1.21, Go may automatically download a different version of Go.
Disable this behavior so that entire pipelines use only one version.

The "go" and "toolchain" directives indicate the minimum version of Go
required when importing and developing the module, respectively. We are
concerned only with compatibility, so downgrade "toolchain" to 1.22.0.

Issue: PGO-1898
See: https://go.dev/doc/toolchain

Author: cbandy

.github/workflows/codeql-analysis.yaml

@@ -9,6 +9,11 @@ on:
   schedule:
     - cron: '10 18 * * 2'
 
+env:
+  # Use the Go toolchain installed by setup-go
+  # https://github.com/actions/setup-go/issues/457
+  GOTOOLCHAIN: local
+
 jobs:
   analyze:
     runs-on: ubuntu-latest

.github/workflows/lint.yaml

@@ -3,6 +3,11 @@ name: Linters
 on:
   pull_request:
 
+env:
+  # Use the Go toolchain installed by setup-go
+  # https://github.com/actions/setup-go/issues/457
+  GOTOOLCHAIN: local
+
 jobs:
   golangci-lint:
     runs-on: ubuntu-latest

.github/workflows/test.yaml

@@ -7,6 +7,11 @@ on:
       - main
       - master
 
+env:
+  # Use the Go toolchain installed by setup-go
+  # https://github.com/actions/setup-go/issues/457
+  GOTOOLCHAIN: local
+
 jobs:
   go-test:
     runs-on: ubuntu-latest
@@ -35,7 +40,6 @@ jobs:
       - run: ENVTEST_K8S_VERSION="${KUBERNETES#default}" make check-envtest
         env:
           KUBERNETES: "${{ matrix.kubernetes }}"
-          GOEXPERIMENT: nocoverageredesign # https://go.dev/issue/65653
           GO_TEST: go test --coverprofile 'envtest.coverage' --coverpkg ./internal/...
 
       # Upload coverage to GitHub
@@ -71,7 +75,6 @@ jobs:
       - run: make createnamespaces check-envtest-existing
         env:
           PGO_TEST_TIMEOUT_SCALE: 1.2
-          GOEXPERIMENT: nocoverageredesign # https://go.dev/issue/65653
           GO_TEST: go test --coverprofile 'envtest-existing.coverage' --coverpkg ./internal/...
 
       # Upload coverage to GitHub

.github/workflows/trivy.yaml

@@ -7,6 +7,11 @@ on:
       - main
       - master
 
+env:
+  # Use the Go toolchain installed by setup-go
+  # https://github.com/actions/setup-go/issues/457
+  GOTOOLCHAIN: local
+
 jobs:
   licenses:
     runs-on: ubuntu-latest

go.mod

@@ -2,8 +2,6 @@ module github.com/crunchydata/postgres-operator
 
 go 1.22.0
 
-toolchain go1.22.4
-
 require (
 	github.com/go-logr/logr v1.4.2
 	github.com/golang-jwt/jwt/v5 v5.2.1