Feat ipynb validator

[dartanghan]

Added a feature to scan .ipynb (jupyter notebook) files, able to read SQL and PYTHON cells.
This will be very useful for data engineers that want their data products validated.

• Added .ipynb in the README.doc
• Added ipynb in pyproject.toml
• Created ipynb_plugin.py
• Added rules in plugins.yaml

Sample code:

%sql
SET password := "secret"
SELECT :password

%python

@dlt.table
def filtered_taxis():
    password="SQLSERVER"
    username="SQLUSER"
    print("username: ", username)
    print("password: ", password)

Sample result:

File: notebook.ipynb
 Identified issue 1: Hardcoded SQL password in notebook
    Snippet: %sql
SET password := "secret"
SELECT :password
    Line number: 62
    CWE: CWE-798
    Severity: High
...

File: dlt_pipeline.ipynb
 Identified issue 1: Hardcoded credentials in code
    Snippet: password="SQLSERVER"
    username="SQLUSER"
    Line number: 64
    CWE: CWE-798
    Severity: High
...