samples: Add example on creating instance with tags

[dohun-dev]

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Fixes #<issue_number_goes_here> ☕️

If you write sample code, please follow the samples format.

This is dependent on 2.75.0 #2832

[KasiaStrz]

Replace addresses with Markdown links: [Creating and managing tags](https://docs.cloud.google.com/bigtable/docs/tags), same change on lines 158, 159.

Correct links are: https://docs.cloud.google.com/bigtable/docs/tags, https://docs.cloud.google.com/resource-manager/docs/tags/tags-overview

[dohun-dev]

Done

[KasiaStrz]

Nit: labels, tag, key, value are not proper names, hence we spell them in lowercase.

[dohun-dev]

Done.

[KasiaStrz]

if doesn't exist.

[dohun-dev]

Done.

[mutianf]

Alternatively, can we pass in an additional argument in main() to create instance with tag?

And looks like createProdInstance() and createProdInstanceWithTags are almost identical. I think you can pass the bool as an param:

main(String[] args) {
    String projectId = args[0];
    boolean createWithTag = false;
    if (args.size() > 1) {
        boolean createWithTag = Boolean.parseBoolean(args[1]);
    }

    ... 

    instanceAdmin.run(createWithTag);
}

run(boolean createWithTag) {
    createProdInstance(createWithTag);
    ...
}


createProdInstance(boolean createWithTag) {
    ...
          Instance.Builder instanceObjBuilder =
          Instance.newBuilder()
              .setDisplayName(instanceId)
              .setType(Instance.Type.PRODUCTION)
              .putLabels("department", "accounting");
          if (createWithTag) {
                instanceObjBuilder.putTags(tagKey, tagValue);
          }
           Instance instanceObj = instanceObjBuilder.build()
          
    ...
}