"TEMPLATE_IMAGE" is redundant in pipeline_with_dependencies (Dataflow - Flex Template)

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**The issue you're having must be related to a file in this repository.** We are unable to provide assistance for issues unrelated to samples in this repository.

Please include as much information as possible:

## In which file did you encounter the issue?

dataflow/flex-templates/pipeline_with_dependencies/README.md

## Did you change the file? If so, how?

No
## Describe the issue

In the README, while building the Flex template, we define the TEMPLATE_IMAGE variable, but it is not being used in the gcloud command. The variable is created, but there is no mention or usage of it in the README.

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