Fix tooltip displaying incorrect months on Y-axis

[MohammadAshmir786]

Checklist:

• I have read freeCodeCamp's contribution guidelines.
• My pull request has a descriptive title (not a vague title like Update index.md)

• Closes Tooltip text issue in the Visualize Data with a Heat Map in the Data Visualization Project. #611

Summary:

This PR fixes an issue where the tooltip was displaying incorrect months for the corresponding data points on the Y-axis.

• Months on the Y-axis: The tooltip was showing the wrong month values for the data points on the Y-axis. This issue has been addressed, and the correct month is now displayed for each data point.

Changes:

• Updated the tooltip logic to correctly reflect the month corresponding to the Y-axis value.

Impact:

This fix ensures that the tooltip now accurately displays the correct month for the data points on the Y-axis.

Testing:

• Manually tested the tooltip for all data points on the Y-axis.
• Verified that the correct month is now displayed in the tooltip for the Y-axis values.