vid is being set to NaN in recent tracker version

[jakeberesford-palmetto]

Describe the bug
Tracking events sent using this tracker are failing in enrichment with the following failure message

{
  "expectation": "cannot be converted to java.lang.Integer",
  "field": "vid",
  "value": "NaN"
}

I suspect this commit causes the issue: b212eb7#diff-e1e232ecf4c494ec3be5f942f973200db624f9569d1776b35781614dcf2a97a8R97

To Reproduce

1. Send a tracking event without calling setSessionIndex or setSessionId
2. Observe the vid p is set to NaN

Expected behavior

vid is not set if sessionIndex is undefined

Desktop (please complete the following information):

• OS: Linux/ubuntu
• Browser: Node.js
• Version: v3.12 (though it seems the bug may have been introduced in 3.11)

Additional context

We are using this package server-side in a node.js application.

[igneel64]

Hey @jakeberesford-palmetto , thanks for spotting that, we released v3.12.1 which hopefully resolves this issue !

[jakeberesford-palmetto]

Thanks for the quick turnaround @igneel64 - much appreciated!