Update attrs from 18.1.0 to 18.2.0 (#3976)

requirements/dev.txt

@@ -44,9 +44,9 @@ isort==4.3.4 \
 atomicwrites==1.2.0 \
     --hash=sha256:6b5282987b21cd79151f51caccead7a09d0a32e89c568bd9e3c4aaa7bbdf3f3a \
     --hash=sha256:e16334d50fe0f90919ef7339c24b9b62e6abaa78cd2d226f3d94eb067eb89043
-attrs==18.1.0 \
-    --hash=sha256:4b90b09eeeb9b88c35bc642cbac057e45a5fd85367b985bd2809c62b7b939265 \
-    --hash=sha256:e0d0eb91441a3b53dab4d9b743eafc1ac44476296a2053b6ca3af0b139faf87b
+attrs==18.2.0 \
+    --hash=sha256:ca4be454458f9dec299268d472aaa5a11f67a4ff70093396e1ceae9c76cf4bbb \
+    --hash=sha256:10cbf6e27dbce8c30807caf056c8eb50917e0eaafe86347671b57254006c3e69
 more-itertools==4.3.0 \
     --hash=sha256:fcbfeaea0be121980e15bc97b3817b5202ca73d0eae185b4550cbfce2a3ebb3d \
     --hash=sha256:c187a73da93e7a8acc0001572aebc7e3c69daf7bf6881a2cea10650bd4420092 \