fix: stop returning when err so diagram can be rendered post error fix

[ad1992]

📑 Summary

Currently in production if for any reason an error occurs, the diagram gets stuck and isn't rendered even after error is fixed hence I have fixed that in this PR

eg, try with below code and config in prod vs this PR

flowchart TD
    A[Christmas] -->|Get money| B(Go shopping)
    B --> C{Let me think}
    C -->|One| D[Laptop]
    C -->|Two| E[iPhone]
    C -->|Three| F[fa:fa-car Car]

{
"theme": "default",
"maxEdges": "10"

change the config to 2 and change it back to 10 -> In prod the diagrams will not rerender until refresh.

• 📖 have read the contribution guidelines
• 💻 have added unit/e2e tests (if appropriate)
• 🔖 targeted develop branch

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[ad1992]

cc @sidharthv96

[ad1992]

friendly reminder @sidharthv96

[sidharthv96]

If return is removed, error is set as false immediately. So something else needs to be changed.