doc: prefer make test-only when verifying the build

PR-URL: https://github.com/nodejs/node/pull/18061
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>
Reviewed-By: Khaidi Chu <i@2333.moe>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>

BUILDING.md

@@ -94,7 +94,7 @@ Depending on host platform, the selection of toolchains may vary.
 
 ### Unix/macOS
 
-Prerequisites:
+#### Prerequisites
 
 * `gcc` and `g++` 4.9.4 or newer, or
 * `clang` and `clang++` 3.4.2 or newer (macOS: latest Xcode Command Line Tools)
@@ -120,6 +120,8 @@ directory and the symbolic `node` link in the project's root directory.
 On FreeBSD and OpenBSD, you may also need:
 * libexecinfo
 
+#### Building Node.js
+
 To build Node.js:
 
 ```console
@@ -138,13 +140,26 @@ for more information.
 Note that the above requires that `python` resolve to Python 2.6 or 2.7
 and not a newer version.
 
-To run the tests:
+#### Running Tests
+
+To verify the build:
+
+```console
+$ make test-only
+```
+
+At this point, you are ready to make code changes and re-run the tests.
+
+If you are running tests prior to submitting a Pull Request, the recommended
+command is:
 
 ```console
 $ make test
 ```
 
-At this point you are ready to make code changes and re-run the tests!
+`make test` does a full check on the codebase, including running linters and
+documentation tests.
+
 Optionally, continue below.
 
 To run the tests and generate code coverage reports:
@@ -166,6 +181,8 @@ reports:
 $ make coverage-clean
 ```
 
+#### Building the documentation
+
 To build the documentation:
 
 This will build Node.js first (if necessary) and then use it to build the docs: