doc: update acid test

macOS_Catalina.md

@@ -17,14 +17,28 @@ If `ProductVersion` is less then `10.15` then this document is not for you. Norm
 
 ### The acid test
 To see if `Xcode Command Line Tools` is installed in a way that will work with `node-gyp`, run:
-1. `/usr/sbin/pkgutil --packages | grep CL`
-    * `com.apple.pkg.CLTools_Executables` should be listed. If it isn't, this test failed.
-2. `/usr/sbin/pkgutil --pkg-info com.apple.pkg.CLTools_Executables`
-    * `version: 11.0.0` (or later) should be listed. If it isn't, this test failed.
-
-If both tests succeeded, _you are done_! You should be ready to install `node-gyp`.
+```
+/usr/sbin/pkgutil --pkgs |
+  grep -i com.apple.pkg.cltools |
+  head -n1 |
+  xargs -n1 /usr/sbin/pkgutil --pkg-info
+```
+
+Test output format is:
+```
+package-id: com.apple.pkg.CLTools_Executables
+version: 11.4.1.0.1.1586360307
+volume: /
+location: /
+install-time: 1587769775
+groups: com.apple.FindSystemFiles.pkg-group
+```
+**`version: 11.0.0` (or later) should be listed.**
+
+If test did not produce any output
+or expected version isn't listed, there is a problem with your Xcode Command Line Tools installation. [Continue to Solutions](#Solutions).
 
-If either test failed, there is a problem with your Xcode Command Line Tools installation. [Continue to Solutions](#Solutions). 
+If test succeeded, _you are done_! You should be ready to install `node-gyp`.
 
 ### Solutions
 There are three ways to install the Xcode libraries `node-gyp` needs on macOS. People running Catalina have had success with some but not others in a way that has been unpredictable.