V10 Fixup GitHub CodeSpaces / VSCode Remote Container (#12882)

* Remove SQL Server part of the CodeSpace - we have SQLite to use

* Update to use .NET 6 and simplified docker stuff

https://github.com/microsoft/vscode-dev-containers/

* Need to set the SQLite Connection string env variable

* Path to SLN has changed to the root of the repo

* Fix up launch and VSCode tasks

.vscode/tasks.json

@@ -54,7 +54,7 @@
             "type": "process",
             "args": [
                 "build",
-                "${workspaceFolder}/src/umbraco.sln",
+                "${workspaceFolder}/umbraco.sln",
                 "/property:GenerateFullPaths=true",
                 "/consoleloggerparameters:NoSummary"
             ],
@@ -69,6 +69,7 @@
             "args": [
                 "watch",
                 "run",
+                "--project",
                 "${workspaceFolder}/src/Umbraco.Web.UI/Umbraco.Web.UI.csproj",
                 "/property:GenerateFullPaths=true",
                 "/consoleloggerparameters:NoSummary"