report: remove unnecessary return in setters

Barring shenanigans like Object.getOwnPropertyDescriptor(), return
values from a setter function will always be inaccessible. Remove
the `return` statements as they can be misleading, suggesting that the
return value is accessible and perhaps used somewhere.

lib/internal/process/report.js

@@ -34,14 +34,14 @@ const report = {
   },
   set directory(dir) {
     validateString(dir, 'directory');
-    return nr.setDirectory(dir);
+    nr.setDirectory(dir);
   },
   get filename() {
     return nr.getFilename();
   },
   set filename(name) {
     validateString(name, 'filename');
-    return nr.setFilename(name);
+    nr.setFilename(name);
   },
   get signal() {
     return nr.getSignal();
@@ -51,7 +51,7 @@ const report = {
     convertToValidSignal(sig); // Validate that the signal is recognized.
     removeSignalHandler();
     addSignalHandler(sig);
-    return nr.setSignal(sig);
+    nr.setSignal(sig);
   },
   get reportOnFatalError() {
     return nr.shouldReportOnFatalError();
@@ -60,7 +60,7 @@ const report = {
     if (typeof trigger !== 'boolean')
       throw new ERR_INVALID_ARG_TYPE('trigger', 'boolean', trigger);
 
-    return nr.setReportOnFatalError(trigger);
+    nr.setReportOnFatalError(trigger);
   },
   get reportOnSignal() {
     return nr.shouldReportOnSignal();
@@ -80,7 +80,7 @@ const report = {
     if (typeof trigger !== 'boolean')
       throw new ERR_INVALID_ARG_TYPE('trigger', 'boolean', trigger);
 
-    return nr.setReportOnUncaughtException(trigger);
+    nr.setReportOnUncaughtException(trigger);
   }
 };