remove go 1.7, 1.8 from circleci

Author: funny-falcon

.circleci/config.yml

@@ -41,17 +41,6 @@ jobs:
     docker:
       - image: circleci/golang:1.9
 
-  "1.8":
-    <<: *test
-    docker:
-      - image: circleci/golang:1.8
-
-  "1.7":
-    <<: *test
-    docker:
-      - image: circleci/golang:1.7
-
-
 workflows:
   version: 2
   build:
@@ -61,5 +50,3 @@ workflows:
       - "1.11"
       - "1.10"
       - "1.9"
-      - "1.8"
-      - "1.7"