Use npm instead of tarball for the geostyler-css-parser

[allyoucanmap]

Description

We are installing the geostyler-css-parser via tarball but we should use npm instead. Check if the pending PR has been merged at the time this issue is in progess. If it's not merged we should move the branch used by tarball under the geosolutions-it repository and create a new package @geosolutions/geostyler-geocss-parser and replace the import where needed.

MapStore2/package.json

Line 128 in e15c98d

"geostyler-geocss-parser": "https://github.com/allyoucanmap/geostyler-geocss-parser/tarball/build",

What kind of improvement you want to add? (check one with "x", remove the others)

• Other... Please describe: Library dependency

Other useful information

[allyoucanmap]

We should also take into account following related libraries and evaluate if the fork is needed:

• geostyler-style
• geostyler-sld-parser
• geostyler-openlayers-parser
• flat-geo-css

[allyoucanmap]

see also this #6933 (comment)