Ensure the ADB-injected CA is not writable by anybody

Because of an ADB bug, user perms are always copied and used as
group & other perms, so this means we have to make it not
writable by _anybody_.

Author: pimterry

src/interceptors/android/android-adb-interceptor.ts

@@ -150,7 +150,7 @@ export class AndroidAdbInterceptor implements Interceptor {
                 deviceId,
                 stringAsStream(certContent.replace('\r\n', '\n')),
                 certPath,
-                0o644
+                0o444
             );
 
             await injectSystemCertificate(this.adbClient, deviceId, rootCmd, certPath);