invert the glob patterns in .vscodeignore to not include untracked files

This prevents `vsce package` from including files that are not tracked
by git. These new glob patterns will ensure that the files that have
been explicitly included in the package.

.vscodeignore

@@ -1,17 +1,10 @@
-.github/**
-.vscode/**
-.vscode-test/**
-out/test/**
-src/**
-.gitignore
-.prettierignore
-eslint.config.mjs
-**/tsconfig.json
-**/tslint.json
-**/*.map
-**/*.ts
-node_modules
-src
-*.lock
-package-lock.json
-tsconfig.json
+**
+!images/zig-icon.png
+!images/example.png
+!syntaxes/zig.tmLanguage.json
+!language-configuration.json
+!out/extension.js
+!package.json
+!LICENSE
+!README.md
+!CHANGELOG.md