Enable all linters by default

This removes the directive from .golangci.yml to disable all linters,
and fixes the relevant bugs / issues that are exposed.

cmd/virtual-kubelet/internal/commands/providers/provider.go

@@ -47,7 +47,6 @@ func NewCommand(s *provider.Store) *cobra.Command {
 				}
 				fmt.Fprintln(cmd.OutOrStdout(), args[0])
 			}
-			return
 		},
 	}
 }

cmd/virtual-kubelet/internal/commands/root/tracing_register_jaeger.go

@@ -40,7 +40,7 @@ func NewJaegerExporter(opts TracingExporterOptions) (trace.Exporter, error) {
 		},
 	}
 
-	if jOpts.Endpoint == "" && jOpts.AgentEndpoint == "" {
+	if jOpts.Endpoint == "" && jOpts.AgentEndpoint == "" { // nolint:staticcheck
 		return nil, errors.New("Must specify either JAEGER_ENDPOINT or JAEGER_AGENT_ENDPOINT")
 	}
 

cmd/virtual-kubelet/internal/provider/mock/mock.go

@@ -329,7 +329,7 @@ func (p *MockProvider) GetPods(ctx context.Context) ([]*v1.Pod, error) {
 }
 
 func (p *MockProvider) ConfigureNode(ctx context.Context, n *v1.Node) {
-	ctx, span := trace.StartSpan(ctx, "mock.ConfigureNode") //nolint:ineffassign
+	ctx, span := trace.StartSpan(ctx, "mock.ConfigureNode") // nolint:staticcheck,ineffassign
 	defer span.End()
 
 	n.Status.Capacity = p.capacity()
@@ -429,7 +429,7 @@ func (p *MockProvider) nodeDaemonEndpoints() v1.NodeDaemonEndpoints {
 // GetStatsSummary returns dummy stats for all pods known by this provider.
 func (p *MockProvider) GetStatsSummary(ctx context.Context) (*stats.Summary, error) {
 	var span trace.Span
-	ctx, span = trace.StartSpan(ctx, "GetStatsSummary") //nolint: ineffassign
+	ctx, span = trace.StartSpan(ctx, "GetStatsSummary") //nolint: ineffassign,staticcheck
 	defer span.End()
 
 	// Grab the current timestamp so we can report it as the time the stats were generated.