fix(agent-task/shared): add CapiClientFunc helper

Signed-off-by: Babak K. Shandiz <babakks@github.com>

pkg/cmd/agent-task/shared/capi.go

@@ -0,0 +1,23 @@
+package shared
+
+import (
+	"github.com/cli/cli/v2/pkg/cmd/agent-task/capi"
+	"github.com/cli/cli/v2/pkg/cmdutil"
+)
+
+func CapiClientFunc(f *cmdutil.Factory) func() (capi.CapiClient, error) {
+	return func() (capi.CapiClient, error) {
+		cfg, err := f.Config()
+		if err != nil {
+			return nil, err
+		}
+
+		httpClient, err := f.HttpClient()
+		if err != nil {
+			return nil, err
+		}
+
+		authCfg := cfg.Authentication()
+		return capi.NewCAPIClient(httpClient, authCfg), nil
+	}
+}