Update devcontainer.json

.devcontainer/devcontainer.json

@@ -30,6 +30,7 @@
                 "streetsidesoftware.code-spell-checker",
                 "alistairchristie.open-reusables",
                 "AlistairChristie.version-identifier",
+                "peterbe.ghdocs-goer",
                 "GitHub.copilot",
                 "GitHub.copilot-chat"
             ]