bug: randomzied contraction's random components can collide with isolated vertices ids #911

Describe the bug
There is a small but real chance that random component ids from the GF2 ax + b can collide with ids of isolated vertices. As a result isolated vertices can get wrong labels.

To Reproduce
.

Expected behavior

System [please complete the following information]:

• OS: e.g. [Ubuntu 18.04]
• Python Version (if applied): [e.g. Python 3.8]
• Spark / PySpark version: [e.g. PySpark 3.5.1]
• GraphFrames version: [e.g. graphframes-0.9.0]

Component

• Scala Core Internal
• Scala API
• Spark Connect Plugin
• PySpark Classic
• PySpark Connect

Additional context
For the use_label_as_components it is not a problem (groupping is applied before the join). Overall should be enough to call once the axpb on isolated vertices to compute component ID instead of using vertex ID.

Are you planning on creating a PR?

• I'm willing to make a pull-request