Add Documentation Hint for Template Job Creation in DataflowRunner

[gayatrikate04]

This PR resolves #18217 by improving the SDK documentation for DataflowPipelineOptions and DataflowRunner.
Changes Made:
Added a hint to the setTemplateLocation method, clarifying its role in creating template jobs in Google Dataflow.
Addressed potential confusion caused by the removal of DataflowTemplateRunner.
Enhanced documentation to improve developer experience and save time.

Let me know if any further improvements are needed. Thanks!

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[gayatrikate04]

Hi there,
I’m working on a pull request, but I’ve run into an issue with the PreCommit Spotless check — it’s failing due to some formatting problems. The issue is that I’m unable to run the Spotless plugin locally, as it doesn’t seem to be configured in the project’s pom.xml file.

Since I can’t modify the pom.xml myself, I wanted to reach out for some advice. Here’s what I was wondering:

• If the Spotless plugin needs to be added to the pom.xml, could someone help configure it or let me know if that’s something I should wait for the maintainers to do?
• Alternatively, if there’s a way to format the code correctly without modifying the pom.xml, I’d really appreciate any tips or guidance on how to get the PreCommit Spotless check to pass.

Here’s a quick example of what the Spotless plugin configuration looks like, just in case it’s helpful:

<build>
  <plugins>
    <plugin>
      <groupId>com.diffplug.spotless</groupId>
      <artifactId>spotless-maven-plugin</artifactId>
      <version>2.12.0</version> <!-- latest version -->
      <executions>
        <execution>
          <goals>
            <goal>apply</goal>
          </goals>
        </execution>
      </executions>
    </plugin>
  </plugins>
</build>