fix: remove deprecated options from golangci-lint (#303)

* fix: change deprecated check-shadowing to shadow for govet linter
* fix: remove deprecated allow-leading-space option for nolintlint linter

Author: tomMoulard

.golangci.yml

@@ -7,11 +7,10 @@ linters-settings:
   goimports:
     local-prefixes: github.com/golang-templates/seed
   govet:
-    check-shadowing: true
+    shadow: true
   misspell:
     locale: US
   nolintlint:
-    allow-leading-space: false # require machine-readable nolint directives (with no leading space)
     allow-unused: false # report any unused nolint directives
     require-explanation: true # require an explanation for nolint directives
     require-specific: false # don't require nolint directives to be specific about which linter is being skipped