Update mongo

Changes:

- https://github.com/docker-library/mongo/commit/d7b81e2: Update to 3.6.20

library/mongo

@@ -4,24 +4,24 @@ Maintainers: Tianon Gravi <[email protected]> (@tianon),
              Joseph Ferguson <[email protected]> (@yosifkit)
 GitRepo: https://github.com/docker-library/mongo.git
 
-Tags: 3.6.19-xenial, 3.6-xenial, 3-xenial
-SharedTags: 3.6.19, 3.6, 3
+Tags: 3.6.20-xenial, 3.6-xenial, 3-xenial
+SharedTags: 3.6.20, 3.6, 3
 # see http://repo.mongodb.org/apt/ubuntu/dists/xenial/mongodb-org/3.6/multiverse/
 Architectures: amd64, arm64v8
-GitCommit: 1fe97dd9ab8e8db7224a84345583bb415d83f602
+GitCommit: d7b81e278d4b1f5e8c3011e397d4f918070aea3a
 Directory: 3.6
 
-Tags: 3.6.19-windowsservercore-ltsc2016, 3.6-windowsservercore-ltsc2016, 3-windowsservercore-ltsc2016
-SharedTags: 3.6.19-windowsservercore, 3.6-windowsservercore, 3-windowsservercore, 3.6.19, 3.6, 3
+Tags: 3.6.20-windowsservercore-ltsc2016, 3.6-windowsservercore-ltsc2016, 3-windowsservercore-ltsc2016
+SharedTags: 3.6.20-windowsservercore, 3.6-windowsservercore, 3-windowsservercore, 3.6.20, 3.6, 3
 Architectures: windows-amd64
-GitCommit: 48df1464cd062f431183c0447d08c720d1947ae6
+GitCommit: d7b81e278d4b1f5e8c3011e397d4f918070aea3a
 Directory: 3.6/windows/windowsservercore-ltsc2016
 Constraints: windowsservercore-ltsc2016
 
-Tags: 3.6.19-windowsservercore-1809, 3.6-windowsservercore-1809, 3-windowsservercore-1809
-SharedTags: 3.6.19-windowsservercore, 3.6-windowsservercore, 3-windowsservercore, 3.6.19, 3.6, 3
+Tags: 3.6.20-windowsservercore-1809, 3.6-windowsservercore-1809, 3-windowsservercore-1809
+SharedTags: 3.6.20-windowsservercore, 3.6-windowsservercore, 3-windowsservercore, 3.6.20, 3.6, 3
 Architectures: windows-amd64
-GitCommit: 48df1464cd062f431183c0447d08c720d1947ae6
+GitCommit: d7b81e278d4b1f5e8c3011e397d4f918070aea3a
 Directory: 3.6/windows/windowsservercore-1809
 Constraints: windowsservercore-1809