Introduce the tools.deps project type

[arichiardi]

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Before submitting the PR make sure the following things have been done (and denote this
by checking the relevant checkboxes):

• The commits are consistent with our [contribution guidelines][1]
• The new code is not generating bytecode or M-x checkdoc warnings
• You've updated the changelog (if adding/changing user-visible functionality)
• You've updated the readme (if adding/changing user-visible functionality)

The new inf-clojure-tools-deps-cmd will be used when the deps.edn file is going
to be detected in the project root.