Update config for golangci

Signed-off-by: Friedrich Gonzalez <1517449+friedrichg@users.noreply.github.com>

Author: friedrichg

.golangci.yml

@@ -6,7 +6,8 @@ run:
     - require_docker
 
 output:
-  format: line-number
+  formats:
+    - format: line-number
 
 linters:
   enable:
@@ -17,6 +18,6 @@ linters:
 
 linters-settings:
   errcheck:
-    exclude: .errcheck-exclude
+    exclude-functions: []
   goimports:
     local-prefixes: "github.com/cortexproject/cortex-tools"