Bazel Credential Helper Bugfix Time Format Issue (#633)

* Bugfix Time Format Issue

Bugfix time conversion issue when converting from time.RFC3339 to time.UnixDate as this
is problematic because RFC3339 is a standardized, unambiguous format with timezone
information (e.g., "2023-01-01T12:00:00Z"), while UnixDate is a human-readable
format without explicit timezone indicators (e.g., "Sun Jan 1 12:00:00 GMT 2023").
This conversion can lead to timezone ambiguity and parsing errors in systems
expecting RFC3339 format, potentially causing authentication failures.

Convert to UTC to avoid parsing errors when timezone can't be determined.

* Incorporate Review Feedback

Switch to much simpler construct..

Author: fitzner

go/cmd/bazelcredswrapper/main.go

@@ -54,8 +54,16 @@ func main() {
 		log.Error(err)
 		os.Exit(1)
 	}
+
+	// Time format conversion note: Converting from time.RFC3339 to time.UnixDate is
+	// problematic because RFC3339 is a standardized, unambiguous format with timezone
+	// information (e.g., "2023-01-01T12:00:00Z"), while UnixDate is a human-readable
+	// format without explicit timezone indicators (e.g., "Sun Jan 1 12:00:00 GMT 2023").
+	// This conversion can lead to timezone ambiguity and parsing errors and potentially
+	// causing authentication failures.
+	// Convert to UTC to avoid parsing errors when timezone can't be determined.
 	fmt.Printf(`{"headers":%s, "token":"%s", "expiry":"%s"}`, jsonHdrs,
-		"", expiry.Format(time.UnixDate))
+		"", expiry.UTC().Format(time.UnixDate))
 }
 
 type CredshelperOut struct {