parsing v7.0.0 no StringLike class

[jamesdbrock]

Description of the change

Upgrade parsing dependency to v7.0.0, remove the StringLike class. https://github.com/purescript-contrib/purescript-parsing/releases/tag/v7.0.0

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Checklist:

• [x] Added the change to the changelog's "Unreleased" section with a link to this PR and your username
• [x] Linked any existing issues or proposals that this pull request should close
• [x] Updated or added relevant documentation in the README and/or documentation directory
• [x] Added a test for the contribution (if applicable)

[thomashoneyman]

We need to update the Bower file dependency to v7.0.0 but otherwise 👍