Increase node max available memory in Build JS Bundles job

[fluiddot]

Increases the max available memory that node can use. This follows the same approach applied in #6503 to avoid CI failures when building Gutenberg, which requires more memory than the default value (2GB).

To test:

• Observe that all CI checks pass.
• Observe in a1bc23e that the heap size is set to 4G (reference).

PR submission checklist:

• I have considered adding unit tests where possible.
• I have considered if this change warrants user-facing release notes more info and have added them to RELEASE-NOTES.txt if necessary.

[fluiddot]

I removed this common parameter as it's no longer used in the pipeline configuration.

[geriux]

LGTM! Thanks for addressing this 🚀