Remove references to "bwrs" #2195

Squashed commit of the following:

commit 1bdf1c7954e0731c95703d10118f3874ab5155d3
Merge: 8ba6e61f 7257251
Author: Daniel García <dani-garcia@users.noreply.github.com>
Date:   Sun Jan 23 23:40:17 2022 +0100

    Merge branch 'remove-bwrs' of https://github.com/RealOrangeOne/vaultwarden into RealOrangeOne-remove-bwrs

commit 7257251ecf23af18deb894e8f2e5519a15360c76
Author: Jake Howard <git@theorangeone.net>
Date:   Thu Jan 6 17:48:18 2022 +0000

    Use `or_else` to save potentially unnecessary function call

commit 40ae81dd3c43a596375d5bfdcc00053e786328cc
Author: Jake Howard <git@theorangeone.net>
Date:   Wed Jan 5 21:18:24 2022 +0000

    Move $BWRS_VERSION fallback into build.rs

commit 743ef74b307a662960f3ca1b9636f3608506516d
Author: Jake Howard <git@theorangeone.net>
Date:   Sat Jan 1 23:08:27 2022 +0000

    Revert "Add feature to enable use of `Option::or` in const context"

    This reverts commit fe8e043b8aaf77c083747bf11760f29b53df0bba.

    We want to run on stable soon, where these features are not supported

commit a1f0da638c8b6ba32209318b105bde1efdd47082
Author: Jake Howard <git@theorangeone.net>
Date:   Sat Jan 1 13:04:47 2022 +0000

    Rename web vault version file

    https://github.com/dani-garcia/bw_web_builds/pull/58

commit fe8e043b8aaf77c083747bf11760f29b53df0bba
Author: Jake Howard <git@theorangeone.net>
Date:   Sat Jan 1 12:56:44 2022 +0000

    Add feature to enable use of `Option::or` in const context

commit 687435c8b2b995e90bf6f0ee619bc305e37bc183
Author: Jake Howard <git@theorangeone.net>
Date:   Sat Jan 1 12:27:28 2022 +0000

    Continue to allow using `$BWRS_VERSION`

commit 8e2f708e5037db8071251c582ebaf1a97d8e5923
Author: Jake Howard <git@theorangeone.net>
Date:   Fri Dec 31 11:41:34 2021 +0000

    Remove references to "bwrs"

    The only remaining one is getting the version of the web vault, which requires coordinating with the web vault patching.