fix: remove the list of default excluded files

[vnhlvn]

In this PR:

• Removes excludedFilesDefault array and its usage in pack.ts

This will actually fix #315 and allow to include any of package-lock.json, pnpm-lock.yaml, yarn.lock, package.json in the final artifact using patterns in serverless.yml.
It won't change the previous behavior as those files are not included unless specified.

[vnhlvn]

@floydspace please take a look 🙏

[vnhlvn]

There's an issue with the e2e:individually test failing because package.json is included in each function packaged individually, regardless of whether package.json is in the patterns or not. The problem occurs when the test tries to unzip two archives into the same folder. Since package.json is in both archives, it asks for permission to overwrite the file.

Also, if we were to keep the default list of excluded files only for individual packaging, it causes issues when package.json is added to the global patterns in serverless.yaml. In this situation, yarn struggles to parse production dependencies due to "serverless-esbuild": "file:../.." in the .esbuild folder, causing an error.

A possible solution is to remove devDependencies from package.json after copying it to the .esbuild folder and to change the unzip command to only extract the handler's file. This approach should help fix both the file conflict and the dependency parsing problems.