bpo-38490: statistics: Add covariance, Pearson's correlation, and simple linear regression (#16813)

Co-authored-by: Tymoteusz Wołodźko <twolodzko+gitkraken@gmail.com
diff --git a/Misc/ACKS b/Misc/ACKS
index 760d6c7..7d9af85 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -1927,6 +1927,7 @@
 Klaus-Juergen Wolf
 Dan Wolfe
 Richard Wolff
+Tymoteusz Wołodźko
 Adam Woodbeck
 William Woodruff
 Steven Work