[Extension Development] parsing exception in "when" clause should default to not showing corresponding entry

<!-- ⚠️⚠️ Do Not Delete This! bug_report_template ⚠️⚠️ --> <!-- Please read our Rules of Conduct: https://opensource.microsoft.com/codeofconduct/ --> <!-- 🕮 Read our guide about submitting issues: https://github.com/microsoft/vscode/wiki/Submitting-Bugs-and-Suggestions --> <!-- 🔎 Search existing issues to avoid creating duplicates. --> <!-- 🧪 Test using the latest Insiders build to see if your issue has already been fixed: https://code.visualstudio.com/insiders/ --> <!-- 💡 Instead of creating your report here, use 'Report Issue' from the 'Help' menu in VS Code to pre-fill useful information. --> <!-- 🔧 Launch with `code --disable-extensions` to check. --> Does this issue occur when all extensions are disabled?: N/A <!-- 🪓 If you answered No above, use 'Help: Start Extension Bisect' from Command Palette to try to identify the cause. --> <!-- 📣 Issues caused by an extension need to be reported directly to the extension publisher. The 'Help > Report Issue' dialog can assist with this. --> - VS Code Version: 1.77.0 - OS Version: Windows 11 Steps to Reproduce: We had an old extension - not actively worked on in a while. that defined a view/item/context like so: "define a chat icon to show up for our extension"  **Behavior:** Not sure if there was a recent change that made the regex in quotes invalid. This was causing the context icon to show up in all other views within VS Code even outside of our extension. This "chat icon" is displayed in other parts of vcode: for example the Remote Explorer View  **Expected** Not a huge deal that the regex in string is invalid after the recent update to 1.77. But our team feels that a parsing exception in a "when" clause should "disable it to make it obvious that something went wrong" rather than "show up …