docs(api): clarify in docs that Well.has_tip checks only for unused t…

…ips (#17412)

Closes RQA-3790

# Overview

`Well.has_tip` property has been checking for only clean/ unused tips since API
v2.2 but the docstrings don't mention that. That has understandably
caused some confusion in protocol behaviors. This PR helps mitigate that
issue by clarifying the exact behavior of this property

## Risk assessment

None.

---------

Co-authored-by: Max Marrone <[email protected]>

api/src/opentrons/protocol_api/labware.py

@@ -117,8 +117,23 @@ def parent(self) -> Labware:
     @property
     @requires_version(2, 0)
     def has_tip(self) -> bool:
-        """Whether this well contains a tip. Always ``False`` if the parent labware
-        isn't a tip rack."""
+        """Whether this well contains an unused tip.
+
+        From API v2.2 on:
+
+        - Returns ``False`` if:
+
+          - the well has no tip present, or
+          - the well has a tip that's been used by the protocol previously
+
+        - Returns ``True`` if the well has an unused tip.
+
+        Before API v2.2:
+
+        - Returns ``True`` as long as the well has a tip, even if it is used.
+
+        Always ``False`` if the parent labware isn't a tip rack.
+        """
         return self._core.has_tip()
 
     @has_tip.setter