Enable the unicorn/prefer-optional-catch-binding ESLint plugin rule

According to MDN this format is available in all browsers/environments that we currently support, see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/try...catch#browser_compatibility

Please also see https://github.com/sindresorhus/eslint-plugin-unicorn/blob/main/docs/rules/prefer-optional-catch-binding.md

test/integration/scripting_spec.js

@@ -471,7 +471,7 @@ describe("Interaction", () => {
             await page._client.send("Page.setDownloadBehavior", {
               behavior: "deny",
             });
-          } catch (_) {}
+          } catch {}
           await clearInput(page, getSelector("47R"));
           await page.evaluate(_ => {
             window.document.activeElement.blur();

test/unit/api_spec.js

@@ -168,7 +168,7 @@ describe("api", function () {
 
         // Shouldn't get here.
         expect(false).toEqual(true);
-      } catch (reason) {
+      } catch {
         expect(true).toEqual(true);
         await destroyed;
       }

test/unit/crypto_spec.js

@@ -549,7 +549,7 @@ describe("CipherTransformFactory", function () {
     try {
       const factory = new CipherTransformFactory(dict, fileId, password);
       expect("createCipherTransform" in factory).toEqual(true);
-    } catch (ex) {
+    } catch {
       // Shouldn't get here.
       expect(false).toEqual(true);
     }

test/unit/evaluator_spec.js

@@ -368,7 +368,7 @@ describe("evaluator", function () {
 
         // Shouldn't get here.
         expect(false).toEqual(true);
-      } catch (_) {
+      } catch {
         expect(!!result.fnArray && !!result.argsArray).toEqual(true);
         expect(result.fnArray.length).toEqual(0);
       }
@@ -389,7 +389,7 @@ describe("evaluator", function () {
 
         // Shouldn't get here.
         expect(false).toEqual(true);
-      } catch (_) {
+      } catch {
         expect(true).toEqual(true);
       }
     });

test/webserver.js

@@ -90,7 +90,7 @@ WebServer.prototype = {
       // Windows paths cause issues in statFile and serverDirectoryIndex.
       // Converting to unix path would avoid platform checks in said functions.
       pathPart = pathPart.replaceAll("\\", "/");
-    } catch (ex) {
+    } catch {
       // If the URI cannot be decoded, a `URIError` is thrown. This happens for
       // malformed URIs such as `http://localhost:8888/%s%s` and should be
       // handled as a bad request.