DOC: Minor fix to docstring formatting for head() and tail() (#58589)

* Minor fix to docstring formatting

Fix minor inconsistency in docstring formatting for `head()` and `tail()`.

Fix the code formatting for the `n` variable appearing in the docstrings of `head()` and `tail()` so that it is consistent with surrounding uses of the variable.

* Update pandas/core/generic.py

---------

Co-authored-by: Matthew Roeschke <10647082+mroeschke@users.noreply.github.com>

Author: albanie

pandas/core/generic.py

@@ -5527,7 +5527,7 @@ def head(self, n: int = 5) -> Self:
         it returns an empty object. When ``n`` is negative, it returns
         all rows except the last ``|n|`` rows, mirroring the behavior of ``df[:n]``.
 
-        If n is larger than the number of rows, this function returns all rows.
+        If ``n`` is larger than the number of rows, this function returns all rows.
 
         Parameters
         ----------
@@ -5615,7 +5615,7 @@ def tail(self, n: int = 5) -> Self:
         For negative values of `n`, this function returns all rows except
         the first `|n|` rows, equivalent to ``df[|n|:]``.
 
-        If n is larger than the number of rows, this function returns all rows.
+        If ``n`` is larger than the number of rows, this function returns all rows.
 
         Parameters
         ----------