feat(analyticsdata): add samples for metadata requests

[anweshan]

No description provided.

[snippet-bot]

Here is the summary of changes.

You are about to add 4 region tags.

• analyticsdata/src/get_common_metadata.php:30, tag analyticsdata_get_common_metadata
• analyticsdata/src/get_common_metadata.php:68, tag analyticsdata_print_get_metadata_response
• analyticsdata/src/get_metadata_by_property_id.php:30, tag analyticsdata_get_metadata_by_property_id
• analyticsdata/src/get_metadata_by_property_id.php:68, tag analyticsdata_print_get_metadata_response

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