Fix header level in settings.md

Change-Id: Ic4ecd583ce62e624dad568f9c421a87e4d222fd4
GitHub-Last-Rev: 0a4f186beb7774134bd7e400c90b4dd6e129a899
GitHub-Pull-Request: golang/tools#180
Reviewed-on: https://go-review.googlesource.com/c/tools/+/203157
Reviewed-by: Ian Cottrell <iancottrell@google.com>
diff --git a/gopls/doc/settings.md b/gopls/doc/settings.md
index 33d01ac..4c70b91 100644
--- a/gopls/doc/settings.md
+++ b/gopls/doc/settings.md
@@ -40,7 +40,7 @@
 
 Default: `"SynopsisDocumentation"`.
 
-## **usePlaceholders** *boolean*
+### **usePlaceholders** *boolean*
 
 If true, then completion responses may contain placeholders for function parameters or struct fields.
 
@@ -64,7 +64,7 @@
 
 Default value: `true`.
 
-**completeUnimported** *boolean*
+### **completeUnimported** *boolean*
 
 If true, the completion engine is allowed to make suggestions for packages that you do not currently import.