Python: No dep installation by default for everyone

As announced in https://github.blog/changelog/2024-01-23-codeql-2-16-python-dependency-installation-disabled-new-queries-and-bug-fixes/ we have turned on this feature flag for github.com already.

This change ensures that users on GHES also has this feature enabled by
default.

Author: RasmusWL

lib/feature-flags.js

@@ -105,7 +105,7 @@ export const featureConfig: Record<
     // here!
     envVar: "CODEQL_ACTION_DISABLE_PYTHON_DEPENDENCY_INSTALLATION",
     minimumVersion: "2.16.0",
-    defaultValue: false,
+    defaultValue: true,
   },
 };