DOC: fix PR02 for pandas.Grouper (#59259)

Author: tuhinsharma121

ci/code_checks.sh

@@ -70,7 +70,6 @@ if [[ -z "$CHECK" || "$CHECK" == "docstrings" ]]; then
         --format=actions \
         -i ES01 `# For now it is ok if docstrings are missing the extended summary` \
         -i "pandas.Series.dt PR01" `# Accessors are implemented as classes, but we do not document the Parameters section` \
-        -i "pandas.Grouper PR02" \
         -i "pandas.MultiIndex.append PR07,SA01" \
         -i "pandas.MultiIndex.copy PR07,RT03,SA01" \
         -i "pandas.MultiIndex.drop PR07,RT03,SA01" \

pandas/core/groupby/grouper.py

@@ -72,6 +72,9 @@ class Grouper:
         Currently unused, reserved for future use.
     **kwargs
         Dictionary of the keyword arguments to pass to Grouper.
+
+    Attributes
+    ----------
     key : str, defaults to None
         Groupby key, which selects the grouping column of the target.
     level : name/number, defaults to None