Improve tests for `JournalStorage`

[porink0424]

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Reference Issues/PRs

Follow up PR of #860

What does this implement/fix? Explain your changes.

• Improved the parsing error handling in JournalStorage:
  • The implementation was designed so that even a single error line would cause the entire system to crash, but error lines can now be pushed into errors variables to prevent it.
• Added tests for JournalStorage:
  • Checking studies including Infinity, -Infinity, NaN.
  • Checking if the system does not crash even when lines that cannot be parsed are included in the file.

Reference

• Node Test runner