chore: remove unused deps, and fix docs issue

[dutterbutter]

Summary of changes
Changes introduced in this pull request:

• Fixes doc issue by updating rust-toolchain.toml
• Removes unused deps

Reference issue to close (if applicable)

Closes #225

[codecov-commenter]

Codecov Report

Merging #232 (628d757) into main (6bf9f21) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #232   +/-   ##
=======================================
  Coverage   82.05%   82.05%           
=======================================
  Files          85       85           
  Lines        5964     5964           
=======================================
  Hits         4894     4894           
  Misses       1070     1070           

Impacted Files	Coverage Δ
standalone/runtime/src/lib.rs	0.00% <ø> (ø)

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