docs: update region tag for the storage quickstart

[shollyman]

This sample uses the wrong prefix, which associates it to BQ rather than
BQ storage.

[snippet-bot]

You are about to delete the following sample browser page.

• samples/snippets/src/main/java/com/example/bigquerystorage/StorageSample.java:19, tag bigquery_storage_quickstart(usage: page 1).

---

Here is the summary of changes.

You are about to add 1 region tag.

• samples/snippets/src/main/java/com/example/bigquerystorage/StorageSample.java:19, tag bigquerystorage_quickstart

You are about to delete 1 region tag.

• samples/snippets/src/main/java/com/example/bigquerystorage/StorageSample.java:19, tag bigquery_storage_quickstart

---

This comment is generated by snippet-bot.
If you find problems with this result, please file an issue at:
https://github.com/googleapis/repo-automation-bots/issues.
To update this comment, add snippet-bot:force-run label or use the checkbox below:

• Refresh this comment

[codecov]

Codecov Report

Merging #985 (c6ff001) into master (17bfbd8) will increase coverage by 0.07%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master     #985      +/-   ##
============================================
+ Coverage     81.10%   81.17%   +0.07%     
  Complexity     1047     1047              
============================================
  Files            78       78              
  Lines          5669     5669              
  Branches        436      436              
============================================
+ Hits           4598     4602       +4     
+ Misses          884      880       -4     
  Partials        187      187              

Impacted Files	Coverage Δ	Complexity Δ
...e/cloud/bigquery/storage/v1beta2/StreamWriter.java	84.17% <0.00%> (+0.91%)	33.00% <0.00%> (ø%)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 17bfbd8...c6ff001. Read the comment docs.