Support bicep style parameters file

### Description

Currently only ARM type parameters files (like https://github.com/Azure/mpf/blob/main/samples/bicep/aks-private-subnet-invalid-params.json) are supported even for bicep executions. 

Pure bicep files currently result in error:

**Unsupported parameter file format below**

```
param prefix = 'bami'
param suffix = 'test'
```

This format should be supported