chore: release rust agent 0.20.0

[smallstepman]

Description

• feat: support for custom HTTP headers asset canister configuration in ic-assets  #359
• feat(ic-asset): configurable dot-directories and -files inclusion #361
• chore: release v0.4.0 ic-types#19
  • fix: specify repository field so that crates.io links to it ic-types#18
  • refactor: Principal overhaul ic-types#17
  • refactor: Faster copy loop ic-types#16
  • fix: Converting long bytes ending in 0x04 to Principal is ok. ic-types#15
  • refactor: remove const_panic ic-types#14
  • chore: Update sha2 dep to 0.10.1 ic-types#12
  • fix: display only ASCII graphic blobs as strings ic-types#11
• release candid#360
  • fix clippy candid#359
  • Candid UI update candid#358
  • chore: use ic-types 0.4 candid#357
  • fix semicolon in rust binding candid#355
  • fix semicolon in did parser candid#354
  • chore: add CODEOWNERS candid#352
  • Add the community maintained Dart library ic_tools. candid#351
  • Fix error candid example. candid#350
  • Rust: derive Copy, Eq, Default for Reserved candid#344
  • Remove space candid#343
  • Fix candid tools package.json error candid#342
  • fix hexnum tokenizer candid#340

How Has This Been Tested?

Both agent-rs PRs are unit tested.

Checklist:

• The title of this PR complies with Conventional Commits.
• I have edited the CHANGELOG accordingly.
• I have made corresponding changes to the documentation.

[smallstepman]

oops, missed that one

• chore: Upgrade to candid 0.7.15 and ic-types 0.4.0 #362

should get merged first