change labelFontUrl to fontUrl for cluster

[ljehezkiel]

PR Checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[x] Refactoring (no functional changes, no api changes)
[x] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Other... Please describe:

What is the current behavior?

Issue Number: N/A
Literally this is first time I contribute in github and pardon my english
I am modifying a line of code where if labelFontUrl is signed, label on cluster didn't work just like node label, it still show squareboxes

Literally just some typo in Cluster.js <Label> where should be fontUrl not labelFontUrl

What is the new behavior?

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[ljehezkiel]

Hi, just ask when will this merged PR can be release?

[amcdnl]

Going out today@!

[ljehezkiel]

@amcdnl Hi, just kindly reminder
can we know when is the release of this update?