[FR]: s3_sync: Add support to provide the name of the destination file

[hashken]

What is the current behavior?

Right now, we are able to provide the bucket and prefix to which a file should be copied to. But, the name of the file remains the same as what is given as input.

Describe the feature

• When we copy a file to s3, sometimes we want to be able to control the name of the file that is uploaded.
• If the file name is static, it's easy to first use copy_file to rename it and then invoke s3_sync.
• But, if we want the file name to be stamped, there is currently no way to achieve this.
• Provide the ability to pass the destination file name
  • Might be nice to have 2 separate args like filename and filename_file, so that we can either directly give the static name or use expand_template to populate the stamped name in a file.
• We should do a check that / is not present in the filename as that would make part of it as a prefix.