fix: Disable telemetry by default in tests (#3200)

I also noticed we don't have `goleak` enabled for CLI tests, this commit
adds it, but commented out. The reason being that we're nowhere near
being able to enable it yet.

Co-authored-by: Cian Johnston <cian@coder.com>

cli/root.go

@@ -1,6 +1,7 @@
 package cli
 
 import (
+	"flag"
 	"fmt"
 	"net/url"
 	"os"
@@ -175,6 +176,10 @@ func versionCmd() *cobra.Command {
 	}
 }
 
+func isTest() bool {
+	return flag.Lookup("test.v") != nil
+}
+
 // createClient returns a new client from the command context.
 // It reads from global configuration files if flags are not set.
 func createClient(cmd *cobra.Command) (*codersdk.Client, error) {