enable gofumpt, goimports, testifylint linters (#551)

Signed-off-by: Matthieu MOREL <[email protected]>

Author: mmorel-35

.golangci.yml

@@ -1,19 +1,41 @@
 linters:
   enable:
     - errorlint
+    - gofumpt
+    - goimports
     - misspell
     - revive
+    - testifylint
 
 issues:
   exclude-rules:
     - path: _test.go
       linters:
         - errcheck
+  max-issues-per-linter: 0
+  max-same-issues: 0
 
 linters-settings:
+  goimports:
+    local-prefixes: github.com/prometheus/common
   revive:
     rules:
       # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#unused-parameter
       - name: unused-parameter
         severity: warning
         disabled: true
+  testifylint:
+    disable:
+      - float-compare
+      - go-require
+    enable:
+      - bool-compare
+      - compares
+      - empty
+      - error-is-as
+      - error-nil
+      - expected-actual
+      - len
+      - require-error
+      - suite-dont-use-pkg
+      - suite-extra-assert-call