Remove web preset dependency on @neutrinojs/image-minify

[edmorley]

Since it increases the yarn install time significantly due to the number of compiled packages and yarnpkg/yarn#932. The feature is disabled by default, however this is still a breaking change so would need to wait until Neutrino 9.

See:
#673 (comment)

[timkelty]

At the same time, lets consider if it is worth it to continue the aggregate @neutrinojs/minify, or if they should just exist separately.

[timkelty]

Related issues and discussion with "default" minification: #678, #673

[ftes]

Also valuable to avoid compilations on CI servers which may not have required build tools.

E.g. the mozjpeg build requires autoreconf, and the pngquant build requires libpng-dev.

✖ Error: autoreconf -fiv && ./configure --disable-shared --prefix=".../node_modules/mozjpeg/vendor" ... && make --jobs=8 && make install --jobs=8
/bin/sh: autoreconf: command not found

✖ Error: pngquant failed to build, make sure that libpng-dev is installed

[edmorley]

Fixed by #815 which will be in Neutrino 9.