EB Sample modification for Xray Getting-Started Example

[Ramneek-kalra]

Issue #, if available:
Current EB Sample isn't applicable for AL1 which is causing all the users of XRay for not getting example of "Getting Started" working properly. Giving below error:

Resource handler returned message: "No Platform named 'arn:aws:elasticbeanstalk:ap-southeast-1::platform/Node.js running on 64bit Amazon Linux' found. (Service: ElasticBeanstalk, Status Code: 400, Request ID: 2ab062a4-b3ca-4b6c-9010-7b4141221ffe)" (RequestToken: f420a69a-dde3-4e9d-7e64-2cf0772a961b, HandlerErrorCode: InvalidRequest)

Description of changes:
To fix this, requesting for this PR to be merged so that sample can be corrected asap for the XRay Service Users with smooth onboarding via Getting Started Example. Below are the changes being done in the attached Zip Code:

1. In the final YAML of CFN Template which is being populated in the guide need to be updated with below new PlatformARN as below:
   =======
   PlatformArn:
   Fn::Join:
   - ":"
   - - arn:aws:elasticbeanstalk
   - Ref: AWS::Region
   - :platform/Node.js 16 running on 64bit Amazon Linux 2/5.6.2
   =======

(Platform Name, can be fetched using: aws elasticbeanstalk list-available-solution-stacks for configured AWS CLI Region)

2. namespace need to be updated in .ebextensions > options.config as below:
   =======
   aws:elasticbeanstalk:environment:proxy:staticfiles:
   /static: /static
   =======

[Reference: Serving Static Files | AL2]

myapp.zip

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[Ramneek-kalra]

Please note, the CFN Template is to be replaced on AWS Console at: https://.console.aws.amazon.com/cloudwatch/home?region=#xray:sample-app