Add note about different series lengths to Series.corr and Series.cov docs (#47145)

* add to corr docs

* add to cov docs

* fix typo

Author: jackgoldsmith4

pandas/core/series.py

@@ -2541,6 +2541,8 @@ def quantile(self, q=0.5, interpolation="linear"):
     def corr(self, other, method="pearson", min_periods=None) -> float:
         """
         Compute correlation with `other` Series, excluding missing values.
+        The two `Series` objects are not required to be the same length and will be
+        aligned internally before the correlation function is applied.
 
         Parameters
         ----------
@@ -2613,6 +2615,8 @@ def cov(
     ) -> float:
         """
         Compute covariance with Series, excluding missing values.
+        The two `Series` objects are not required to be the same length and
+        will be aligned internally before the covariance is calculated.
 
         Parameters
         ----------