requirements: Move to atomicwrites==1.4.1

As explained upstream:
https://github.com/untitaker/python-atomicwrites/issues/61 there is no
longer a 1.3.0 version but the API is unchanged.  Move to 1.4.1.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/test/py/requirements.txt b/test/py/requirements.txt
index 33c5c0b..2d0fcc9 100644
--- a/test/py/requirements.txt
+++ b/test/py/requirements.txt
@@ -1,4 +1,4 @@
-atomicwrites==1.3.0
+atomicwrites==1.4.1
 attrs==19.3.0
 coverage==4.5.4
 extras==1.0.0