updated head and tail docstrings (#46466)

* updated head and tail docstrings

* fixed typos

Author: INDIG0N

pandas/core/generic.py

@@ -5284,6 +5284,8 @@ def head(self: NDFrameT, n: int = 5) -> NDFrameT:
         For negative values of `n`, this function returns all rows except
         the last `n` rows, equivalent to ``df[:-n]``.
 
+        If n is larger than the number of rows, this function returns all rows.
+
         Parameters
         ----------
         n : int, default 5
@@ -5357,6 +5359,8 @@ def tail(self: NDFrameT, n: int = 5) -> NDFrameT:
         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.
+
         Parameters
         ----------
         n : int, default 5