[NFC] Correct a comment.

Author: hageboeck

tree/dataframe/src/RMetaData.cxx

@@ -114,8 +114,8 @@ int RMetaData::GetI(const std::string &key, int defaultVal) const
       throw std::logic_error("Metadata value found at key '" + key + "' is not of type int.");
    return fJson->payload[key].get<int>();
 }
-/// @brief Return the metadata value of type int given the key, a default int metadata value if the key is not found, or
-/// an error if the metadata value is of a non-double type.
+/// @brief Return the metadata value of type double given the key, a default double metadata value if the key is not
+/// found, or an error if the metadata value is of a non-double type.
 /// @param[in] key input key for a given RMetaData instance.
 /// @param[in] defaultVal metadata value of type double which is read as default while a given key cannot be found in
 /// the dataset.