fix: run --parallel

fixes a regression in v5.5.4

.changeset/forty-hounds-yawn.md

@@ -0,0 +1,5 @@
+---
+"@pnpm/default-reporter": patch
+---
+
+Fixes a regression published in pnpm v5.5.3 as a result of nullish coalescing refactoring.

packages/default-reporter/src/reporterForClient/index.ts

@@ -59,7 +59,7 @@ export default function (
       throttleProgress: opts.throttleProgress,
     }),
     reportLifecycleScripts(log$, {
-      appendOnly: opts.appendOnly ?? opts.streamLifecycleOutput,
+      appendOnly: opts.appendOnly === true || opts.streamLifecycleOutput,
       cwd,
       width,
     }),