Docs: specify minimum SAM CLI version in `examples/sam` readme file

[dreamorosi]

What were you searching in the docs?

@shdq was trying to deploy the SAM examples and ran into issues around the version of the CLI required to run the example.

The SAM examples using nodejs18.x runtime, this version was introduced in v1.65.0 (source), so users running earlier versions will get a Runtime not supported error.

Is this related to an existing documentation section?

No response

How can we improve?

The README file of the example should have a section that specifies the minimum version required to run the sample.

Got a suggestion in mind?

Add the following wording:

AWS SAM CLI version 1.65 or later. If you have an older version of the AWS SAM CLI, see Upgrading the AWS SAM CLI.

To this section of the readme.

Acknowledgment

• I understand the final update might be different from my proposed suggestion, or refused.