Update README: typo fix and update IDF version

[SwapnilPande]

Description

Small Readme updates to note that this template supports IDF v6.6.0 and a typo fix

Motivation and Context

Updated documentation is always good

How has this been tested?

No tests

Screenshots (if appropriate, e.g. schematic, board, console logs, lab pictures):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update
• Hardware (schematic, board, system design) change
• Software change

Checklist:

• My change requires a change to the documentation.
• I have added / updated the documentation related to this change via either README or WIKI

Software

• I have added tests to cover my changes.
• I have updated the .github/workflows/build.yml file to add my new test to the automated cloud build github action.
• All new and existing tests passed.
• My code follows the code style of this project.

Hardware

• I have updated the design files (schematic, board, libraries).
• I have attached the PDFs of the SCH / BRD to this PR
• I have updated the design output (GERBER, BOM) files.

[github-actions]

✅Static analysis result - no issues found! ✅