Compiler downloader

[Nathan-SL]

Usage related changes

• Closes Replace dockerized cairo compiler by relying on prebuilt GitHub binaries #398
• If the user specifies a custom cairo1BinDir, this is used. If the compilerVersion is specified in the hardhat config file, this is used. These two options cannot be specified at the same time (there is a runtime check). If the user doesn't specify any, the last compiler version compatible with the plugin is used.
• If the user specifies a compilerVersion and it is not present, we download it for the user and store it in ~/.starknet-hardhat-plugin. If already present here (and executable), we use that.

Development related changes

• Removed condition (and indentation) in setup-compiler.sh
• Extract common testing functionality by introducing assertCompilationArtifactsExist
• In starknet-wrapper.ts, the compilation functions are moved to the abstract parent class (StarknetWrapper)
  • The usefulness of starknet wrapper keeps on decreasing.

Checklist:

• Formatted the code
• No linter errors + tried to avoid introducing linter warnings
• Performed a self-review of the code
• Rebased to the last commit of the target branch (or merged it into my branch)
• Documented the changes
• Updated the test directory (with a test case consisting of network.json, hardhat.config.ts, check.ts)
• Linked issues which this PR resolves
• Created a PR (Wont affect this PR) to the plugin branch of starknet-hardhat-example:Compiler downloader starknet-hardhat-example#120
• All tests are passing (for external contributors who don't have access to the CI/CD pipeline)

[FabijanC]

Does it work for compiling files outside of the repo? Was this case supported with older compiler?

[FabijanC]

Needs conflict resolution. There are still three unresolved conversations, I marked the others as resolved.

[FabijanC]

Approving to make GitHub stop indicating that changes are requested. Assigning another reviewer.