feat: #1552 Add EfsMountTarget and EfsFileSystem as resource (also fixes #1609)

[d-aggarwal]

Added EfsMountTarget as resource and fixed mount target fetch logic

Related issues or links

#1552

Checklist

Provide proof that this works (this makes reviews move faster). Please perform one or more of the following:

• [x] Update/add unit or integration tests.
• [x] Include a screenshot showing what the graph looked like before and after your changes.
• [x] Include console log trace showing what happened before and after your changes.

If you are changing a node or relationship:

• [x] Update the schema and readme.

If you are implementing a new intel module:

• [x] Use the NodeSchema data model.

Relationship between EfsFileSystem and EfsMountTarget

[d-aggarwal]

i have fixed the issues, kindly review @achantavy

[d-aggarwal]

Hi @jychp , when you get a chance, kindly review this PR. Thanks!

[d-aggarwal]

LGTM

I have added region in docs of schema