Update pypy

Changes:

- https://github.com/docker-library/pypy/commit/784e896: Update to 7.3.1, pip 20.2.3

library/pypy

@@ -6,20 +6,20 @@ GitRepo: https://github.com/docker-library/pypy.git
 
 Tags: 2.7-7.3.1, 2.7-7.3, 2.7-7, 2.7, 2-7.3.1, 2-7.3, 2-7, 2, 2.7-7.3.1-buster, 2.7-7.3-buster, 2.7-7-buster, 2.7-buster, 2-7.3.1-buster, 2-7.3-buster, 2-7-buster, 2-buster
 Architectures: amd64, arm64v8, i386
-GitCommit: f326d2a8970649cd6308f7a8f0467eeb5c6fc4f8
+GitCommit: 784e896a5d09a6e5139926936b897ee779fcce77
 Directory: 2.7
 
 Tags: 2.7-7.3.1-slim, 2.7-7.3-slim, 2.7-7-slim, 2.7-slim, 2-7.3.1-slim, 2-7.3-slim, 2-7-slim, 2-slim, 2.7-7.3.1-slim-buster, 2.7-7.3-slim-buster, 2.7-7-slim-buster, 2.7-slim-buster, 2-7.3.1-slim-buster, 2-7.3-slim-buster, 2-7-slim-buster, 2-slim-buster
 Architectures: amd64, arm64v8, i386
-GitCommit: f326d2a8970649cd6308f7a8f0467eeb5c6fc4f8
+GitCommit: 784e896a5d09a6e5139926936b897ee779fcce77
 Directory: 2.7/slim
 
 Tags: 3.6-7.3.1, 3.6-7.3, 3.6-7, 3.6, 3-7.3.1, 3-7.3, 3-7, 3, latest, 3.6-7.3.1-buster, 3.6-7.3-buster, 3.6-7-buster, 3.6-buster, 3-7.3.1-buster, 3-7.3-buster, 3-7-buster, 3-buster, buster
 Architectures: amd64, arm64v8, i386, ppc64le, s390x
-GitCommit: f326d2a8970649cd6308f7a8f0467eeb5c6fc4f8
+GitCommit: 784e896a5d09a6e5139926936b897ee779fcce77
 Directory: 3.6
 
 Tags: 3.6-7.3.1-slim, 3.6-7.3-slim, 3.6-7-slim, 3.6-slim, 3-7.3.1-slim, 3-7.3-slim, 3-7-slim, 3-slim, slim, 3.6-7.3.1-slim-buster, 3.6-7.3-slim-buster, 3.6-7-slim-buster, 3.6-slim-buster, 3-7.3.1-slim-buster, 3-7.3-slim-buster, 3-7-slim-buster, 3-slim-buster, slim-buster
 Architectures: amd64, arm64v8, i386, ppc64le, s390x
-GitCommit: f326d2a8970649cd6308f7a8f0467eeb5c6fc4f8
+GitCommit: 784e896a5d09a6e5139926936b897ee779fcce77
 Directory: 3.6/slim