[meld/ui-next] Update dev requirements to handle conditional typing imports

[Kai Willadsen <kaiw src gnome org>]

commit 5ab185a6b8dea7f320b676e6dbd94d54038a7a22
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Sun Mar 3 07:32:49 2019 +1000

    Update dev requirements to handle conditional typing imports

 dev-requirements.txt | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/dev-requirements.txt b/dev-requirements.txt
index 7528bc8d..3f89718a 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -1,6 +1,6 @@
-flake8==3.5.0
+flake8==3.7.5
 flake8-import-order==0.16
 mccabe==0.6.1
 pep8-naming==0.4.1
-pycodestyle==2.3.1
-pyflakes==1.6.0
+pycodestyle==2.5.0
+pyflakes==2.1.0