InlineCompletionItem of type SnippetString does not support brace completion

[juihanamshet1]

Does this issue occur when all extensions are disabled?: Yes/No

Version: 1.71.0 (system setup)
Commit: 784b017
Date: 2022-09-01T07:36:10.600Z
Electron: 19.0.12
Chromium: 102.0.5005.167
Node.js: 16.14.2
V8: 10.2.154.15-electron.0
OS: Windows_NT x64 10.0.22000
Sandboxed: No

Steps to Reproduce:

1. Set the inlineCompletionItem.insertText type to be a SnippetString and completeBracketPairs to true
2. The brace completion does not work
3. I looked in the code and saw that bracket completion is only done for when insertText is of type string

cc @hediet