Replace Turbo-Base64 with aklomp/base64

[mkmkme]

Fixes #31643
Fixes #45790
Fixes #41957

Changelog category (leave one):

• Improvement

Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):

Replaced the library to handle (encode/decode) base64 values from Turbo-Base64 to aklomp-base64. Both are SIMD-accelerated on x86 and ARM but 1. the license of the latter (BSD-2) is more favorable for ClickHouse, Turbo64 switched in the meantime to GPL-3, 2. with more GitHub stars, aklomp-base64 seems more future-proof, 3. aklomp-base64 has a slightly nicer API (which is arguably subjective), and 4. aklomp-base64 does not require us to hack around bugs (like non-threadsafe initialization). Note: aklomp-base64 rejects unpadded base64 values whereas Turbo-Base64 decodes them on a best-effort basis. RFC-4648 leaves it open whether padding is mandatory or not, but depending on the context this may be a behavioral change to be aware of.

[mkmkme]

I noticed the build fails on x86_64. I'll fix it and undraft it.

Please keep in mind that as I mentioned earlier, this actually makes base64{Encode,Decode} slower

[robot-clickhouse-ci-1]

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[spff]

I found select tryBase64Decode('aoeo054640eu=') returns non-empty string from 23.9, should we update the doc or should we turn it into empty string?

[rschu1ze]

@spff Thanks for reporting, a fix is here.