build: update coverage Makefile target comments

Update the comments for the `coverage` Makefile target.
- Source files under `lib` are no longer instrumented since
d1dee49
- Fix the name of the related CI job.

PR-URL: #39365
Refs: #25157
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: richardlau

Makefile

@@ -209,11 +209,10 @@ coverage-clean:
 		-type f -exec $(RM) {} \;
 
 .PHONY: coverage
-# Build and test with code coverage reporting.  Leave the lib directory
-# instrumented for any additional runs the user may want to make.
-# For C++ coverage reporting, this needs to be run in conjunction with configure
-#  --coverage.  html coverage reports will be created under coverage/
-# Related CI job: node-test-commit-linux-coverage
+# Build and test with code coverage reporting. HTML coverage reports will be
+# created under coverage/. For C++ coverage reporting, this needs to be run
+# in conjunction with configure --coverage.
+# Related CI job: node-test-commit-linux-coverage-daily
 coverage: coverage-test ## Run the tests and generate a coverage report.
 
 .PHONY: coverage-build