Changed: bug-report-template: scream that this is not the place to report bugs about packages (#3989)

I'm seeing a lot of bug reports that should have been made to
termux/termux-packages, but people don't just read things not written in
BOLD and caps it seems. So now scream out, so that they do read.

Also direct confused users to termux/termux-packages, in case it does
actually belong to termux/termux-app, we can always transfer the issue
there