refactor(3p/lisp/mime4cl): port remaining base64 decoding to qbase64 r/6156

DECODE-BASE64-STREAM-TO-SEQUENCE is the only thing that requires
anything fancy: We read into an adjustable array. Alternative could be
using REDIRECT-STREAM and WITH-OUTPUT-TO-STRING, but that is likely
slower (untested).

Test cases are kept for now to confirm that qbase64 is conforming to our
expectations, but can probably dropped in favor of a few more sample
messages in the test suite.

:START and :END are sadly no longer supported and need to be replaced by
SUBSEQ.

Change-Id: I5928aed7551b0dea32ee09518ea6f604b40c2863
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8586
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Autosubmit: sterni <sternenseemann@systemli.org>

0 files changed, 0 insertions, 0 deletions