Add a new patch written by s0600204, replacing the use of `distutils` with `sysconfig` in the setup of the bundled virtualenv in SpiderMonkey.
Add a patch which is a portion of https://phabricator.services.mozilla.com/D130410, fixing upstream's bug 1739486 on Fedora.
This fixes build issues on recent Debian and Fedora. This is consistent with upstream's upcoming changes in ESR102 following the deprecation of `distutils`.
This cleans up some old SM patches; renames the unicode one; move a Python-related environment variable inside `build.sh`.