Block Bindings: Update render tests

[ockham]

Backport of changes made to the tests in WordPress/gutenberg#71389.

Independently of that PR, I think these changes make sense, since they make the tests less verbose and less redundant.

The changes are basically as follows:

• Use the newly introduced block_bindings_supported_attributes_{$block_name} filter to register a test/block's attribute as supported by Block Bindings, rather than using an actual block (Paragraph) for most tests.
• Merge three test cases that check if get_value_callback works correctly (accepts arguments; correctly includes symbols and numbers; return value is sanitized when rendered) into one, by using a dataProvider.
• Merge two test cases that check if block context is correctly evaluated, and that access is only given to context included in a source's uses_context property.

No semantic changes have been made, at least not deliberately -- the tests should still cover the same expected behavior.

Trac ticket: https://core.trac.wordpress.org/ticket/63840

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Props bernhard-reiter, gziolo.

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[gziolo]

Nice refactoring. Thank you for consolidating similar use cases and extending coverage 👍🏻

[gziolo]

Committed in #60720.