SAM debug fails with layer BuildMethod:makefile

**Describe the bug**

I have a sam application, which has a python lambda function. This lambda function depends on a lambda layer. This layer has a BuildMethod: makefile in its template.yaml definition.
The sam applications builds fine with sam build and can be deployed to AWS and works correctly after being deployed.
However, when I attempt to debug this lambda function locally using vscode, the sam build step fails with "Make Failed: make: *** No rule to make target" error.
During the investigation I executed the statements, which debugger executes manually with --debug switch and compared their output to the regular sam build output.

The correctly executed make statement looks like this:
executing Make: ['make', '--makefile', '/home/test/work/projects/testproject/lambda/shareddepslayer/Makefile', 'build-shareddepslayer']

While the make statement, executed during the debug build is this:
executing Make: ['make', '--makefile', '/tmp/aws-toolkit-vscode/vsctkQvLSJf/debug-requirements.txt', 'build-shareddepslayer']

This suggests that vscode SAM debug build process wrongfully takes a manifest file as a parameter for make instead of Makefile.

**To Reproduce**

1. Create a SAM application with a python lambda function, which depends on the layer
2. Layer shall use BuildMethod: makefile
3. Add Debug Configuration for this function to launch.json
4. Start debugging

**Expected behavior**

SAM build shall succeed and debugging session shall start properly

**Desktop (please complete the following information):**

OS: Linux x64 4.19.128-microsoft-standard
Visual Studio Code Extension Host Version: 1.52.1
AWS Toolkit Version: 1.18.0

Reproduce the VS Code SAM debug build using the template.yaml layer with BuildMethod: makefile, its Makefile, and the launch.json debug configuration. Compare the failing debug command with the successful sam build command, then trace where the debug build selects debug-requirements.txt instead of Makefile. Done means the build uses the layer Makefile and the local debugging session starts successfully.

Written by the indexing model from the issue text.