[Fargate] [EFS]: NFS mount timeo option to adjustable

### Community Note

* Please vote on this issue by adding a 👍 [reaction](https://blog.github.com/2016-03-10-add-reactions-to-pull-requests-issues-and-comments/) to the original issue to help the community and maintainers prioritize this request
* Please do not leave "+1" or "me too" comments, they generate extra noise for issue followers and do not help prioritize the request
* If you are interested in working on this issue or have submitted a pull request, please leave a comment

**Tell us about your request**
There is no way to adjust NFS timeo value other than default 600 (1 minute) while mounting EFS on Fargate's task.

**Which service(s) is this request for?**
Fargate

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
This value is way too long to some customers as this is read/write timeout. Should be able to be adjustable

**Are you currently working around this issue?**
No

**Additional context**
This request is created on behalf of Enterprise customer (Customer can't create github issue byself due to firewall)

**Attachments**

No repository files, tests, or entry points are identified in the issue. Start by reviewing how AWS Fargate mounts EFS and whether the NFS timeo option is exposed; done means customers can adjust the EFS mount timeout instead of being limited to the default 600.

Written by the indexing model from the issue text.