Eslint tweaks (#696)

* make eslint styleguide into warnings & drop no-else-return

* reintroduce max-warnings=0

* remove unnecessary eslint line disable

* reintroduce no-else-return rule

.lintstagedrc.js

 module.exports = {
   "*.{js,ts,tsx}": files => {
     return (
-      "eslint --fix " + files.filter(file => !cli.isPathIgnored(file)).join(" ")
+      "eslint --max-warnings=0 --fix " + files.filter(file => !cli.isPathIgnored(file)).join(" ")
     );
   },
   "*.{css,scss,json,md,html,yml}": ["prettier --write"],

package.json

       "prettier"
     ],
     "rules": {
-      "curly": "error",
+      "curly": "warn",
       "no-console": [
-        "error",
+        "warn",
         {
           "allow": [
             "warn",
           ]
         }
       ],
-      "no-else-return": "error",
-      "no-useless-return": "error",
+      "no-else-return": "warn",
+      "no-useless-return": "warn",
       "prefer-const": [
-        "error",
+        "warn",
         {
           "destructuring": "all"
         }
       ],
-      "prefer-template": "error",
-      "prettier/prettier": "error"
+      "prefer-template": "warn",
+      "prettier/prettier": "warn"
     }
   },
   "homepage": "https://excalidraw.com",

src/clipboard.ts

     const text = e.clipboardData?.getData("text/plain").trim();
     if (text && !PREFER_APP_CLIPBOARD) {
       return { text };
-      // eslint-disable-next-line no-else-return
-    } else {
-      return getAppClipboard();
     }
+    return getAppClipboard();
   } catch (e) {}
 
   return {};