No such file error while using Custom Image for Lambda

[DilLip-Chowdary-Codes]

Are you certain it's a bug?

• [X] Yes, it looks like a bug

Are you using the latest plugin release?

• [X] Yes, I'm using the latest plugin release

Is there an existing issue for this?

• [X] I have searched existing issues, it hasn't been reported yet

Issue description

When we've configured lambda with a custom docker image, and also configured python requirements layer using serverless-python-requirements (of course for custom image functions we can't attach a layer)

Here expected to deploy the application without error, or at least show an error/warning to convey that layers are not supported for custom image functions, instead I got the error.

Here better to add one validation, which will raise an error if we configure the layers for custom image functions.

Service configuration (serverless.yml) content

service: my-service

useDotenv: true

provider:
  name: aws
  runtime: python3.9
  stage: ${opt:stage, 'alpha'}
  apiName: ${self:service}
  region: ap-south-1
  memorySize: 512
  timeout: 60
  lambdaHashingVersion: 20201221
  endpointType: regional
  logs:
    restApi: true
    level: INFO
  deploymentBucket:
    blockPublicAccess: true
    name: ${env:CODE_DEPLOYMENT_BUCKET}
    maxPreviousDeploymentArtifacts: 3

plugins:
  - serverless-python-requirements

custom:
  pythonRequirements:
    slim: true
    useDownloadCache: false
    useStaticCache: false
    layer:
      name: ${self:service}-${self:provider.stage}-requirements-python39
      description: Requirements Lambda layer for My Lambda Function
      compatibleRuntimes:
        - python3.9

  config:
    CODE_DEPLOYMENT_BUCKET: ${env:CODE_DEPLOYMENT_BUCKET}
    DOCKER_IMAGE_NAME: ${env:DOCKER_IMAGE_NAME}
    DOCKER_IMAGE_NAME_WITH_TAG_IN_ECR: ${aws:accountId}.dkr.ecr.${self:provider.region}.amazonaws.com/${self:custom.config.DOCKER_IMAGE_NAME}:${self:provider.stage}

functions:
  debugger_handler:
    image: ${self:custom.config.DOCKER_IMAGE_NAME_WITH_TAG_IN_ECR}
    name: ${self:service}-${self:provider.stage}
    layers:
      - {Ref: PythonRequirementsLambdaLayer}
    events:
      - http:
          path: /mypath/
          method: post
          integration: lambda-proxy
          cors: true

Command name and used flags

serverless deploy --stage alpha

Command output

✖ Stack my-service-alpha failed to deploy (0s)
Environment: linux, node 12.20.1, framework 3.26.0, plugin 6.2.2, SDK 4.3.2
Credentials: Local, "default" profile
Docs:        docs.serverless.com
Support:     forum.serverless.com
Bugs:        github.com/serverless/serverless/issues

Error:
Error: ENOENT: no such file or directory, open '.serverless/requirements.txt'
    at Object.openSync (fs.js:462:3)
    at Object.readFileSync (fs.js:364:35)
    at module.exports (/home/ib-developer/node_modules/sha256-file/index.js:24:19)
    at sha256Path (/home/ib-developer/node_modules/serverless-python-requirements/lib/shared.js:134:10)
    at ServerlessPythonRequirements.zipRequirements (/home/ib-developer/node_modules/serverless-python-requirements/lib/layer.js:16:23)
    at ServerlessPythonRequirements.tryCatcher (/home/ib-developer/node_modules/bluebird/js/release/util.js:16:23)
    at Promise._settlePromiseFromHandler (/home/ib-developer/node_modules/bluebird/js/release/promise.js:547:31)
    at Promise._settlePromise (/home/ib-developer/node_modules/bluebird/js/release/promise.js:604:18)
    at Promise._settlePromiseCtx (/home/ib-developer/node_modules/bluebird/js/release/promise.js:641:10)
    at _drainQueueStep (/home/ib-developer/node_modules/bluebird/js/release/async.js:97:12)
    at _drainQueue (/home/ib-developer/node_modules/bluebird/js/release/async.js:86:9)
    at Async._drainQueues (/home/ib-developer/node_modules/bluebird/js/release/async.js:102:5)
    at Immediate.Async.drainQueues [as _onImmediate] (/home/ib-developer/node_modules/bluebird/js/release/async.js:15:14)
    at processImmediate (internal/timers.js:461:21)

1 deprecation found: run 'serverless doctor' for more details

Environment information

Framework Core: 3.26.0
Plugin: 6.2.2
SDK: 4.3.2

[DilLip-Chowdary-Codes]

@serverless @pgrzesik any update on this?