Avoid removing backslashes from Dockerfiles

foxundermoon/vs-shell-format#29
foxundermoon/vs-shell-format#62
mvdan/sh#424

The foxundermoon/vs-shell-format extension formats Dockerfiles, but it
shouldn't, because the underlying formatter mvdan/sh isn't engineered
for Dockerfiles. As explained in mvdan/sh#424,

> Removing the `\` is correct in shell, because a line ending in `&&`
> just continues the command in the following line.

This commit will disable Dockerfile formatting.

codium/User/settings.json

@@ -95,7 +95,7 @@
   "cSpell.spellCheckDelayMs": 5000,
   "deno.unstable": false,
   "[dockerfile]": {
-    "editor.defaultFormatter": "foxundermoon.shell-format"
+    "editor.formatOnSave": false
   },
   "[dotenv]": {
     "editor.defaultFormatter": "foxundermoon.shell-format"
@@ -150,6 +150,7 @@
     "editor.rulers": [80],
     "files.eol": "\n"
   },
+  "shellformat.effectLanguages": ["shellscript"],
   "[typescript]": {
     "editor.defaultFormatter": "esbenp.prettier-vscode"
   },