Rename default import from mock_apollo_helpers

What does this MR do?

Rename default import from mock_apollo_helpers

• in mock_apollo_helpers, the default export is usually named createMockApollo
• then a utility method called createMockApolloProvider is created to utilize createMockApollo
• naming the imported method createMockApolloProvider could be confusing, so I am renaming it

Does this MR meet the acceptance criteria?

Conformity

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Security

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