Bump mercurial from 5.6 to 5.6.1 (#1989)

Bumps [mercurial](https://mercurial-scm.org/) from 5.6 to 5.6.1.

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

requirements.txt

@@ -5,7 +5,7 @@ joblib==0.17.0
 libmozdata==0.1.68
 lmdb==0.99
 matplotlib==3.3.3
-mercurial==5.6
+mercurial==5.6.1
 microannotate==0.0.23
 mozci==1.11.3
 numpy==1.19.4