2 warning popups when changing toolchain

[award999]

Describe the bug
When changing the selected version of Xcode using the Swift: Select Toolchain... command, you get prompted with 2 warning about needing to reload the extension. Little annoying

To Reproduce
Steps to reproduce the behavior:

1. Run the command and select a different Xcode installation

Expected behavior
Should ideally only have one warning popup

Environment

• OS: macOS
• Swift version: N/A
• Visual Studio Code version: N/A
• vscode-swift version: N/A

Additional context
N/A

[award999]

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