Remove vendor directory and composer.lock from project repository

Bumping this to major because it means that fully updating to H5P 1.25 requires an update to the vendor directory. I've committed an issue that allows update via composer, but that makes the app vendor directory out of sync with the module one 📌 Allow update to H5P editor/core 1.25 Fixed .

H5P uses some css/js from this directory though, so it's not as easy as deleting it, those would have to be included another way. A possible solution would be a build step for the module to extract those files from h5p core and add them in a css/js vendor directory without any of the PHP code though. Maybe just be deleting the PHP files from /vendor?

The /h5p/vendor/ directory can't really be deleted since not only are so many CSS and JS files referenced in code, but it's also in the resize JS link in embeds, so removing it would somewhat break other sites that have embedded an H5P. Also, the composer.json needs to lock down a specific version of the dependencies in order to have a match between the dependencies included in the module's /vendor and the dependencies installed by composer in the project's root /vendor. The merge request in 🐛 Support h5p/h5p-core:1.26 and h5p/h5p-editor:1.25 Needs work deletes the autoloader and all php files included in the module, and keeps the composer.lock file in order for the version installed in the project /vendor to match the CSS and JS shipped with the module's /vendor directory.