Remove unused allow declarations for removed methods

What does this MR do?

These 2 methods (.size_limit and .collapse_limit) appear to have been removed in a5d47bb0. Since these are mocked with an allow directive, the fact that we never invoke them doesn't raise any kind of error or failure.

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Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
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• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
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Security

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