missing arrow head in flowchart(issue inherited from mermaid itself)

[K4zuki]

• reference: https://github.com/knsv/mermaid/issues/544

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due to issue in mermaid CLI (as referred), arrow head in flow chart disappears in output images.

for now up to [email protected] is confirmed working

Could it be possible to limit package dependency up to [email protected]? fix is just remove ^ from package.json.