chore(testutil): add testutil.GoleakOptions (#16070)

- Adds `testutil.GoleakOptions` and consolidates existing options to
this location
- Pre-emptively adds required ignore for this Dependabot PR to pass CI
https://github.com/coder/coder/pull/16066

agent/agent_test.go

@@ -58,7 +58,7 @@ import (
 )
 
 func TestMain(m *testing.M) {
-	goleak.VerifyTestMain(m)
+	goleak.VerifyTestMain(m, testutil.GoleakOptions...)
 }
 
 // NOTE: These tests only work when your default shell is bash for some reason.

agent/agentscripts/agentscripts_test.go

@@ -24,7 +24,7 @@ import (
 )
 
 func TestMain(m *testing.M) {
-	goleak.VerifyTestMain(m)
+	goleak.VerifyTestMain(m, testutil.GoleakOptions...)
 }
 
 func TestExecuteBasic(t *testing.T) {

agent/agentssh/agentssh_test.go

@@ -29,7 +29,7 @@ import (
 )
 
 func TestMain(m *testing.M) {
-	goleak.VerifyTestMain(m)
+	goleak.VerifyTestMain(m, testutil.GoleakOptions...)
 }
 
 func TestNewServer_ServeClient(t *testing.T) {