style(devcontainer): fix typo

Not a all relevant in any case, but still…

.devcontainer/devcontainer.json

@@ -41,6 +41,6 @@
         8080
     ],
     "postCreateCommand": ".devcontainer/postCreateCommand.sh",
-    // alternatiuve: apache2ctl start (but requires root)
+    // alternative: apache2ctl start (but requires root)
     "postAttachCommand": "php -S 0.0.0.0:8080"
 }