fix(tvix/store/nixbase32): fix encoder/decoder r/5781

Replace our data_encoding usage with the implementation taken from
https://github.com/nix-community/go-nix/tree/master/pkg/nixbase32

Also uncomment some of the unit tests, and add a regression test for a
NIXBASE32.encode with a 32 bytes sequence.

The previous implementation of NIXBASE32.encode is wrong in that case:

```
❯ nix hash to-base32 sha256-s6JN6XqP28g1uYMxaVAQMLiXcDG8tUs7OsE3QPhGqzA=
0c5b8vw40dy178xlpddw65q9gf1h2186jcc3p4swinwggbllv8mk
❯ echo -n s6JN6XqP28g1uYMxaVAQMLiXcDG8tUs7OsE3QPhGqzA= | base64 -d | hexdump -C
00000000  b3 a2 4d e9 7a 8f db c8  35 b9 83 31 69 50 10 30  |..M.z...5..1iP.0|
00000010  b8 97 70 31 bc b5 4b 3b  3a c1 37 40 f8 46 ab 30  |..p1..K;:.7@.F.0|
00000020
```

Change-Id: I0468b62bbbab390f8d7d3812e657e5d59dceed59
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7934
Tested-by: BuildkiteCI
Autosubmit: flokli <flokli@flokli.de>
Reviewed-by: Adam Joseph <adam@westernsemico.com>
Reviewed-by: tazjin <tazjin@tvl.su>

0 files changed, 0 insertions, 0 deletions