Dependency updates necessary for node 18

[mmattel]

This PR collects other dependency PR's into one and ugrades to node v18.

Note that when running yarn install, you will get an error: error gulp-squoosh@0.11.0: The engine "node" is incompatible with this module. gulp-squoosh (image compressor) is incompatible with node v18. As replacement could be a library like gulp-sharp-optimize-images.

The affected code location is: tasks/build.js

#79
    gulp.src("img/**/*.{jpg,png}", opts).pipe(
      squoosh(({ width, height, size, filePath }) => ({
        encodeOptions: {
          ...(path.extname(filePath) === ".png"
            ? { oxipng: {} }
            : { mozjpeg: {} }),
        },
      }))
    ),

We need to find a way to modify the code using the new library to fix this.

[mmattel]

Based on support of @DeepDiver1975 we did the following:

• Removal of gulp-squoosh This library was only necessary to compact jpg and png files - honestly, not necessary anymore.
• Let gulp-zip be on version 5.1.0 There is a major change from 5 --> 6 where 6 uses ESM which would impact a gulp redesign.

Next step: local testing

[mmattel]

Local testing went fine: ✔️

• yarn install
• yarn build
• Building the full documenation based on the created ui bundle
• Content testing ok