chore(lint): skips true|false for goconst (opendatahub-io#1110)

As we have labels and annotations with values either `true` or `false`
we often compare them in the code. This leads to complains of `goconst`
linter about extracting these "magic words" to constants. As this are
obvious values to check against there's little benefit of doing so.

This change configures `goconst` for golangci-lint runner to skip such
cases.

(cherry picked from commit 2b7f7da)

.golangci.yml

@@ -15,6 +15,8 @@ linters-settings:
       - dot
     skip-generated: false
     custom-order: true
+  goconst:
+    ignore-strings: "true|false"
   errcheck:
     check-type-assertions: true
   exhaustive: