chore: Dafny test code changes for Python

[lucasmcdonald3]

Issue #, if available:

Description of changes:

• Replace UTF-8 characters with escape characters
  • See Dafny fails with most languages when using characters outside the BMP in string literals with --unicode-char:false dafny-lang/dafny#5737 for context. We've already done this in the MPL.
• Reformat module declarations to make Python and Go's sed'ing easier

Note that this is intended to go into main now.

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[rishav-karanjit]

LGTM

[ajewellamz]

LGTM