Remove ASPNETCORE_ENV variable from setting

src/Razor/src/Microsoft.AspNetCore.Razor.VSCode/src/BlazorDebug/BlazorDebugConfigurationProvider.ts

@@ -17,10 +17,13 @@ export class BlazorDebugConfigurationProvider implements vscode.DebugConfigurati
         const shellArgs = process.platform === 'win32' ? ['/c', 'chcp 65001 >NUL & dotnet run'] : ['run'];
         const spawnOptions = {
             cwd: configuration.cwd || (folder && folder.uri && folder.uri.fsPath),
-            env: {
-                ...process.env,
-                ASPNETCORE_ENVIRONMENT: 'Development',
-            },
+            /**
+             * The VSCode Terminal API expects a the values of the
+             * env object to be `string | null` which conflicts with
+             * the type Node sets on the `process.env` property so
+             * some type coercion is required here.
+             */
+            env: process.env as {[key: string]: string | null},
         };
 
         const output = this.vscodeType.window.createTerminal({