Fixing a smattering of Connection Dialog bugs

[Benjin]

• Fixes Connect Button sometimes gets cut off when connecting to Azure SQL DB #18123 by adding ability to scroll when components overflow
• Fixes No way to refresh recent connections in connection dialog #18121 by adding a refresh button to the MRU connections list
• Fixes Clicking recently-used connection while in "browse Azure" mode should change back to "parameters" mode #18108 by setting the appropriate input mode when an MRU connection is selected

[github-actions]

VSIX Size Comparison

• Main branch VSIX size: 11734 KB
• PR branch VSIX size: 13192 KB
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React Webview Bundle Size Comparison

• Main branch bundle size: 2944 KB
• PR branch bundle size: 2944 KB
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