Update k256 to v0.11 (fixes #1153) on v0.23.x

[tomtau]

and relaxed the crate version bounds

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

[codecov-commenter]

Codecov Report

Merging #1154 (38f7613) into v0.23.x (ea6fd53) will decrease coverage by 0.0%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           v0.23.x   #1154     +/-   ##
=========================================
- Coverage     67.4%   67.4%   -0.1%     
=========================================
  Files          212     212             
  Lines        20280   20284      +4     
=========================================
- Hits         13680   13674      -6     
- Misses        6600    6610     +10     

Impacted Files	Coverage Δ
abci/src/codec.rs	88.8% <0.0%> (-1.3%)	⬇️
tendermint/src/public_key.rs	73.8% <0.0%> (-1.2%)	⬇️
light-client-verifier/src/types.rs	38.2% <0.0%> (-0.6%)	⬇️
testgen/src/header.rs	84.4% <0.0%> (-0.6%)	⬇️
abci/src/server.rs	8.8% <0.0%> (-0.4%)	⬇️
tendermint/src/private_key.rs	23.8% <0.0%> (ø)
tendermint/src/node.rs	63.7% <0.0%> (+0.1%)	⬆️

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[tomtau]

currently, it was only bumped on master: #1129 (i.e. v0.24.x)

[tony-iqlusion]

Not sure what's up with the clippy failure which looks unrelated.

This looks good to me and would unblock some TMKMS use cases as well.

[thanethomson]

Yeah the clippy failure's totally unrelated, probably just due to new lints. I'll fix this in a follow-up.

error: `format!(..)` appended to existing `String`
  --> testgen/src/apalache.rs:70:13
   |
70 |             new_model += &format!("{} == ~{}\n", inv, test.test);
   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: `-D clippy::format-push-string` implied by `-D warnings`
   = help: consider using `write!` to avoid the extra allocation
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#format_push_string

error: could not compile `tendermint-testgen` due to previous error
warning: build failed, waiting for other jobs to finish...
error: could not compile `tendermint-testgen` due to previous error

[tony-iqlusion]

Thank you!