Stripe the spaces during pyproject.toml validation

### Information about bug

Having a leading space in dependency is still a valid check and when running pre build validations it fails.
If app fails in prebuild validation - Show error message for which app and file its failing so that it's easy for users to debug the issue from the stack trace throwing

Support ticket id: 63331

### Steps to Reproduce

Try adding a leading space in pyproject.toml file for the dependencies and it fails during build

### Relevant log output / Stack trace / Full Error Message.

```shell

```

Start by locating the pyproject.toml dependency validation used during pre-build validation and reproduce the failure with a leading space in a dependency. Done means valid dependency spacing is handled and, when validation fails, the error identifies the affected app and file.

Written by the indexing model from the issue text.