Prevent bids values with leading 0s in tests

When used with `run`, the leading 0 gets stripped because run is
converted into an int. This breaks tests that instantiate a datset on
the filesystem and re-parse it using generate_inputs. Easiest solution
is to just to prevent these values entirely

snakebids/tests/strategies.py

@@ -100,6 +100,9 @@ def bids_value(pattern: str = r"[^\n\r]*") -> st.SearchStrategy[str]:
         # remove values leading with multiple dots ".." because pybids doesn't handle
         # them correctly when applied to the "extension" entity
         .filter(lambda s: s[:2] != "..")
+        # numbers with leading 0s get messed up with _run-, which converts to int
+        # and strips the leading 0s. This messes up some of the dataset creation tests
+        .filter(lambda s: s.isdigit() and int(s) > 0 and not s.startswith("0"))
     )