Comply with TOML string requirements

[mattschlebusch]

Reason for this Change

The pre-commit script used to manually parse the key-value pairs in the file, which required strings as unquoted when passed in manually to the rustmt --config ... command. This meant string manipulation when parsing parameters from the tests/fmt.toml file. With the --config-path parameter for rustfmt, it is possible to leave all the string values in the TOML file as quoted.

Description of Changes

• Remove string handling from code that make use of fmt.toml. This requires the use of rustfmt's --config-path option to be able to use the string values as quoted as per the TOML standard.

  • This required the addition of the Rust nightly toolchain in addition to the stable toolchain in the development container.

• Drops the license-template-path formatting parameter as it is no longer supported by the rust toolchain. See github discussion: https://github.com/rust-lang/rustfmt/issues/3352

License Acceptance

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.