[doc] Add warning for empty sequences in 'use-implicit-booleaness-not-comparison'

Author: Pierre-Sassoulas

doc/data/messages/u/use-implicit-booleaness-not-comparison-to-string/details.rst

@@ -1,3 +1,4 @@
 Following this check blindly in weakly typed code base can create hard to debug issues. If the value
-can be something else that is falsey but not a string (for example ``None``, or ``0``), the code will
+can be something else that is falsey but not a string (for example ``None``, an empty sequence, or ``0``),
+the code will
 not be equivalent.

doc/data/messages/u/use-implicit-booleaness-not-comparison-to-zero/details.rst

@@ -1,3 +1,3 @@
 Following this check blindly in weakly typed code base can create hard to debug issues. If the value
-can be something else that is falsey but not an ``int`` (for example ``None``, or an empty string),
-the code will not be equivalent.
+can be something else that is falsey but not an ``int`` (for example ``None``, an empty sequence,
+or an empty string), the code will not be equivalent.

doc/data/messages/u/use-implicit-booleaness-not-comparison/details.rst

@@ -0,0 +1,3 @@
+Following this check blindly in weakly typed code base can create hard to debug issues. If the value
+can be something else that is falsey but not a sequence (for example ``None``, an empty string, or ``0``),
+the code will not be equivalent.