Removing mock-fs promises, rewriting mock async tests

[andrealit]

Description:

After removing mock-fs from the project, remove any uses of mock-fs in the test cases and replace with mock-fs-promise. The two tests that need to be re-reviewed in the future after development are CanvasComponent.spec.tsx and Explorer.spec.tsx.

mock-fs-promise is an internal module that uses tmp-promise to create a temporary directory for holding all mocked filesystem objects (files, directories, and symbolic links). The API for mock-fs-promise mimics the API of mock-fs, but allows for consistent asynchronous access by depending on the standard Node.js fs (which natively supports Promises, callbacks, and async/await). Additionally, since mock-fs-promise is creating real files and directories, it is possible to create initialize a mocked directory as a valid git repository (see Git-Based Tests for an example of this).

This PR resolves #487, and signifies the following version changes:

• MAJOR version increase
• MINOR version increase
• PATCH version increase

Changes:

This PR makes the following changes:

• Removes mock-fs and @types/mock-fs from devDependencies.
• Adds tmp-promise to devDependencies.
• Rewrites all tests that include mock-fs to use mock-fs-promise instead.

Checklist:

Before submitting this PR, I have verified that my code:

• Resides on a fix/ or feature/ branch that was initially branched off from development.
• Passes code linting (yarn lint) and unit testing (yarn test).
• Successfully builds a distribution package (yarn package).

Additionally, I have verified that:

• My name is listed in the Contributors section, or this PR includes a request to add my name.
• I have read and am aware of the CONTRIBUTING guide for this project.

[nelsonni]

Several items need to be addressed before this PR can be approved:

• Update the .gitignore file to include the correct Yarn 2 exclusion rules (per inline comment).
• Remove all of the .yarn/cache/*.zip and related files that would not be included based on the updated .gitignore rules.
• Update package.json to not include @types/mock-fs or memfs (per inline comments).

[nelsonni]

Two minor changes and then this PR is ready:

• Remove .yarn/install-state.gz from git-tracking and don't include in the PR.
• Remove the mock-fs import statement in __test__/CanvasComponent.spec.tsx

[nelsonni]

@andrealit, looks like you missed a mock-fs call in __test__/stacks.spec.ts:

FAIL __test__/stacks.spec.ts
  ● Test suite failed to run

    __test__/stacks.spec.ts:1:18 - error TS7016: Could not find a declaration file for module 'mock-fs'. '/home/runner/work/synectic/synectic/node_modules/mock-fs/lib/index.js' implicitly has an 'any' type.
      Try `npm i --save-dev @types/mock-fs` if it exists or add a new declaration (.d.ts) file containing `declare module 'mock-fs';`

    1 import mock from 'mock-fs';
                       ~~~~~~~~~