Fix: Makefile targets fail when project path contains spaces

[shreyakash24]

Description

Many Makefile targets in OpenCRE fail when the project directory path contains spaces (e.g. ~/git folder/OpenCRE).
This happens because unquoted shell paths are expanded incorrectly by the shell.

Commands such as make e2e, make test, make import-neo4j rely on FLASK_APP and other path-based variables, which are set without proper quoting.

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Steps to Reproduce

1. Clone the repository into a directory with spaces:

   git clone https://github.com/OWASP/OpenCRE.git "~/git folder/OpenCRE"

2. Create and activate a virtual environment inside the project directory:

   python3 -m venv venv
   source venv/bin/activate

3. Run any of the following:

   make test
   make e2e
   make migrate-upgrade
   

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Observed Behavior

• Shell fails to correctly resolve paths containing spaces.
• Error occurs,
  

    /bin/sh: line 0: export: `folder/OpenCRE/cre.py': not a valid identifier
    make: *** [test] Error 1
  

• FLASK_APP points to an invalid path when expanded.

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Expected Behavior

• Makefile targets should work regardless of whether the project path contains spaces.
• Shell commands should correctly resolve paths.

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Suggested fix

Quote path-based variables when exporting them in Makefile targets, for example:

 export FLASK_APP="$(CURDIR)/cre.py"