feat: Migrates the dds-datasets-polyline sample; select changes.

[willum070]

This PR does the following things:

• Migrates the dds-datasets-polyline sample to js-api-samples.
• Refactors UI to be declarative-first.
• Removes all ts-ignore comments.
• Updates to use the weekly channel.
• Updates map IDs and dataset IDs since now data artifacts reside on the maps-docs-team Pantheon project.

[snippet-bot]

Here is the summary of changes.

You are about to add 4 region tags.

• samples/dds-datasets-polyline/index.html:7, tag maps_dds_datasets_polyline
• samples/dds-datasets-polyline/index.ts:7, tag maps_dds_datasets_polyline
• samples/dds-datasets-polyline/index.ts:21, tag maps_dds_datasets_polyline_style_function
• samples/dds-datasets-polyline/style.css:6, tag maps_dds_datasets_polyline

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