Escaping Backslashes when interpolating code content

[jimilp7]

Description

Problem:
Runtime crashes occurred due to improper escaping of backslashes in raw string patterns used in code blocks, exemplified by:

foo = re.match(r'[A-Z]+(\d+)', segments[2])

This resulted in errors such as:

server-1  | KeyError: '\\d'

The root cause was traced back to insufficient backslash escaping in the escaped_code variable during dynamic string operations.

Key Changes:

• Enhanced Backslash Escaping: Updated the escaping mechanism to ensure correct handling of backslashes in dynamically evaluated strings. This change doubles backslashes in escaped_code, preventing runtime errors during regex operations. The adjustment specifically affects the __interpolate_code_content method, where re.sub() is utilized for string replacements.

How to Test:

• Reproduce the Error: Before applying the changes, insert a raw string with an unescaped backslash in any Mage code block and execute it to observe the crash.
• Verify the Fix: After implementing the changes, rerun the same block. The absence of the previous KeyError confirms the correction.

Checklist

• The PR is tagged with proper labels (bug, enhancement, feature, documentation)
• I have performed a self-review of my own code
• I have added unit tests that prove my fix is effective or that my feature works
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation

cc:
@wangxiaoyou1993
@dy46
@tommydangerous