do not invent a name

Nowhere else is this called "Dist check"
diff --git a/src/tests/intro.md b/src/tests/intro.md
index c55d60f..84f99e9 100644
--- a/src/tests/intro.md
+++ b/src/tests/intro.md
@@ -111,7 +111,7 @@
 
 This requires building all of the documentation, which might take a while.
 
-### Dist check
+### `distcheck`
 
 `distcheck` verifies that the source distribution tarball created by the build
 system will unpack, build, and run all tests.