imp(Protobuf)!: alignencode{,_length_delimited}_vec with prost::Message to return Vec<u8>

[Farhad-Shabani]

Closes: #1323

• Referenced an issue explaining the need for the change
• Updated all relevant documentation in docs
• Updated all code comments where relevant
• Wrote tests
• Added entry in .changelog/

[mzabaluev]

Good, annoying unwraps gone!

[codecov-commenter]

Codecov Report

Merging #1324 (5dfc4f5) into main (9854a66) will decrease coverage by 0.1%.
The diff coverage is 93.4%.

❗ Current head 5dfc4f5 differs from pull request most recent head a3540ae. Consider uploading reports for the commit a3540ae to get more accurate results

@@           Coverage Diff           @@
##            main   #1324     +/-   ##
=======================================
- Coverage   59.7%   59.7%   -0.1%     
=======================================
  Files        283     283             
  Lines      26903   26891     -12     
=======================================
- Hits       16087   16073     -14     
- Misses     10816   10818      +2     

Impacted Files	Coverage Δ
tendermint/src/proposal/sign_proposal.rs	40.5% <0.0%> (ø)
tendermint/src/proposal.rs	90.4% <33.3%> (ø)
proto/src/lib.rs	100.0% <100.0%> (ø)
proto/tests/unit.rs	94.8% <100.0%> (ø)
tendermint/src/block/header.rs	99.2% <100.0%> (-0.1%)	⬇️
tendermint/src/public_key.rs	76.3% <100.0%> (ø)
tendermint/src/public_key/pub_key_request.rs	97.3% <100.0%> (ø)
tendermint/src/validator.rs	72.6% <100.0%> (-0.4%)	⬇️
tendermint/src/vote.rs	83.5% <100.0%> (ø)
tendermint/src/vote/sign_vote.rs	96.8% <100.0%> (ø)

... and 3 files with indirect coverage changes

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more