bugfix: restove previous behaviour for cldf validate command

CHANGELOG.md

@@ -3,6 +3,11 @@
 The `pycldf` package adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
 
+## [unreleased]
+
+Fixed issue whereby CLDF Markdown content was validated even if not explicitely requested.
+
+
 ## [1.40.0] - 2024-12-13
 
 - Support certain GitHub URLs as dataset locators.

src/pycldf/commands/validate.py

@@ -26,6 +26,9 @@ def run(args):
     if not cldf.validate(log=args.log):
         return 1
 
+    if not args.with_cldf_markdown:
+        return 0
+
     missing = collections.Counter()
     links = []