[MAINT] Fix codespell error (#186)

examples/compare_coherency_methods.py

@@ -512,7 +512,7 @@ def plot_connectivity_circle():
 # Conclusion
 # ----------
 #
-# Altogether, there are clear scenarious in which different coherency-based
+# Altogether, there are clear scenarios in which different coherency-based
 # methods are appropriate.
 #
 # Methods based on the imaginary part of coherency alone (ImCoh, MIC, MIM)