Upgrade Go version to 1.20 (hashicorp#2898)

* chore: Upgrade Go version

* fix: Upgrade golangci-lint to support 1.20

* fix: Don't use t.SetEnv in parallel tests

This is a panic in Go 1.20 and it sounds like a recipe
for distaster in general.

Author: johanbrandhorst

.go-version

@@ -1 +1 @@
-1.19.4
+1.20

Makefile

@@ -33,7 +33,7 @@ golangci-lint:
 	$(eval GOLINT_INSTALLED := $(shell which golangci-lint))
 
 	if [ "$(GOLINT_INSTALLED)" = "" ]; then \
-		sh scripts/install-golangci-lint.sh -b $(GO_PATH)/bin v1.50.1; \
+		sh scripts/install-golangci-lint.sh -b $(GO_PATH)/bin v1.51.0; \
 	fi;
 
 .PHONY: cleangen

internal/cmd/base/server_test.go

@@ -426,7 +426,6 @@ func TestServer_AddEventerToContext(t *testing.T) {
 }
 
 func TestSetupWorkerPublicAddress(t *testing.T) {
-	t.Parallel()
 	tests := []struct {
 		name             string
 		inputConfig      *config.Config

internal/cmd/config/config_test.go

@@ -1888,7 +1888,6 @@ func TestDatabaseSkipSharedLockAcquisition(t *testing.T) {
 }
 
 func TestSetupControllerPublicClusterAddress(t *testing.T) {
-	t.Parallel()
 	tests := []struct {
 		name                    string
 		inputConfig             *Config