Fix priority inversion issue exposed by Xcode 14

[paulb777]

Fix #10130

[google-oss-bot]

Size Report ¹

Affected Products

• FirebaseDatabase

  Type	Base (0ca75ea)	Merge (169b503)	Diff
  CocoaPods	1.40 MB	1.42 MB	+16.5 kB (+1.2%)

Test Logs

• Base (0ca75ea): https://github.com/firebase/firebase-ios-sdk/actions/runs/2928825000
• Merge (169b503): https://github.com/firebase/firebase-ios-sdk/actions/runs/2935138160

1. https://storage.googleapis.com/firebase-sdk-metric-reports/LE370Q4JPz.html

[google-oss-bot]

Coverage Report ¹

Affected Products

• FirebaseDatabase-iOS-FirebaseDatabase.framework

  Overall coverage changed from 57.03% (0ca75ea) to 57.04% (169b503) by +0.00%.

  Filename	Base (0ca75ea)	Merge (169b503)	Diff
  FSRWebSocket.m	38.43%	38.52%	+0.09%

Test Logs

• Base (0ca75ea): https://github.com/firebase/firebase-ios-sdk/actions/runs/2928825000
• Merge (169b503): https://github.com/firebase/firebase-ios-sdk/actions/runs/2935138160

1. https://storage.googleapis.com/firebase-sdk-metric-reports/yD0aooEKZ1.html

[paulb777]

Upstream followed in facebookincubator/SocketRocket#651