Remove max check labels verification

This should now be done in the API taking into account the particular
tenant limits.

pkg/pb/synthetic_monitoring/checks_extra.go

@@ -41,7 +41,6 @@ var (
 	ErrInvalidCheckFrequency  = errors.New("invalid check frequency")
 	ErrInvalidCheckTimeout    = errors.New("invalid check timeout")
 	ErrInvalidCheckLabelName  = errors.New("invalid check label name")
-	ErrTooManyCheckLabels     = errors.New("too many check labels")
 	ErrInvalidCheckLabelValue = errors.New("invalid check label value")
 	ErrInvalidLabelName       = errors.New("invalid label name")
 	ErrInvalidLabelValue      = errors.New("invalid label value")
@@ -130,7 +129,6 @@ const (
 const (
 	MaxMetricLabels          = 20   // Prometheus allows for 32 labels, but limit to 20.
 	MaxLogLabels             = 15   // Loki allows a maximum of 15 labels.
-	MaxCheckLabels           = 10   // Allow 10 user labels for checks,
 	MaxProbeLabels           = 3    // 3 for probes, leaving 7 for internal use.
 	maxValidLabelValueLength = 2048 // This is the actual max label value length.
 	MaxLabelValueLength      = 128  // Keep this number low so that the UI remains usable.
@@ -406,10 +404,6 @@ func (c Check) validateTimeout() error {
 }
 
 func validateLabels(labels []Label) error {
-	if len(labels) > MaxCheckLabels {
-		return ErrTooManyCheckLabels
-	}
-
 	seenLabels := make(map[string]struct{})
 
 	for _, label := range labels {