fix: `wash build` key directory setting behavior

[ahmedtadde]

Feature or Problem

Despite setting key_directory field in the [actor] section of wasmcloud.toml, wash build will still either reuse or generate a new key in ~/.wash/keys. It appears to the end user that wash build command is ignoring the provided configuration.

Related Issues

620

Release Information

v0.21.1

Consumer Impact

improved correctness of the wash cli; behaves as expected.

Testing

Built on platform(s)

• [ ] x86_64-linux
• [ ] aarch64-linux
• [ ] x86_64-darwin
• [x] aarch64-darwin
• [ ] x86_64-windows

Tested on platform(s)

• [ ] x86_64-linux
• [ ] aarch64-linux
• [ ] x86_64-darwin
• [x] aarch64-darwin
• [ ] x86_64-windows

Acceptance or Integration

added test cases to ensure key directory configuration is respected and adheres to common configuration precedence rule config file field < env var < cli arg

Manual Verification

ran wash build on hello actor template repo with different key directory configuration.

[connorsmith256]

@ahmedtadde LGTM! but there's a minor merge conflict 🙏

[ahmedtadde]

@ahmedtadde LGTM! but there's a minor merge conflict 🙏

branch is now rebased with upstream/main.