Update powerShellAdditionalExePaths to match new schema

PowerShell/vscode-powershell#3978 (comment)

Author: beatcracker

.devcontainer/devcontainer.json

@@ -9,12 +9,10 @@
 		// Otherwise it loads it's own PSScriptAnalyzer assembly,
 		// which prevents build.ps1 from using specific version of PSScriptAnalyzer
 		"powershell.scriptAnalysis.enable": false,
-		"powershell.powerShellAdditionalExePaths":[
-			{
-				"versionName": "latest",
-				"exePath": "/opt/powershell/pwsh"
-			}
-		]
+		"powershell.powerShellAdditionalExePaths": {
+			"versionName": "latest",
+			"exePath": "/opt/powershell/pwsh"
+		}
 	},
 	"extensions": [
 		"ms-vscode.powershell"