Update smwImmersion release for OJS 3.5

[Godoy0722]

No description provided.

[bozana]

Hi @Godoy0722, a few changes a needed here:

• Don't modify the existing 3.5.0.0 <release>. Leave it pointing at v3.5.3.0 and add v3.5.4.0 as a new <release> element (see how other plugins in plugins.xml accumulate releases — old ones stay so installs on every OJS line keep working).
• Bump version.xml in the package to a real, increasing number that matches the tag — <release>3.5.4.0</release> — and give it the correct <date> (it's currently frozen at 1.0.0.0 / 2024-12-30).
• Keep the gallery <release version> identical to the package's version.xml <release> — so the new entry is <release version="3.5.4.0" date="…" md5="..."> pointing at smwImmersion-v3.5.4.0.tar.gz.
  Thanks a lot!