Remove already enforced eslint exceptions

Removes some eslint exceptions for rules we are
already (almost) following anyway.

.eslintrc.js

@@ -1,21 +1,11 @@
 module.exports = {
   extends: [
     "@opencast/eslint-config-ts-react",
-    "react-app/jest"
+    "react-app/jest",
   ],
   rules: {
-    // "always" gives 319 warning, "never" gives 991.
-    "object-curly-spacing": "off",
-
     // Currently 120 warnings.
     "@typescript-eslint/no-explicit-any": "off",
-
-    // `else` in new line is used often, and often an `if` condition is on the
-    // same line as `{`.
-    "brace-style": "off",
-
-    // Until we figure out how to get to React 18
-    "react/no-deprecated": "off",
   },
   overrides: [
     {

src/main/Timeline.tsx

@@ -479,8 +479,7 @@ export const Waveforms: React.FC<{ timelineHeight: number; }> = ({ timelineHeigh
         // Display a flatline
         <div css={{ width: "100%" }}><hr /></div>
       );
-    }
-    else {
+    } else {
       return (
         <>
           <LuLoader css={[spinningStyle, { fontSize: 40 }]} />