fix(sampling): update condition (#198)

Author: dmehala

src/datadog/trace_sampler.cpp

@@ -55,7 +55,7 @@ SamplingDecision TraceSampler::decide(const SpanData& span) {
     decision.limiter_max_per_second = limiter_max_per_second_;
     decision.configured_rate = rule.rate;
     const std::uint64_t threshold = max_id_from_rate(rule.rate);
-    if (knuth_hash(span.trace_id.low) < threshold) {
+    if (knuth_hash(span.trace_id.low) <= threshold) {
       const auto result = limiter_.allow();
       if (result.allowed) {
         decision.priority = int(SamplingPriority::USER_KEEP);
@@ -90,7 +90,7 @@ SamplingDecision TraceSampler::decide(const SpanData& span) {
   }
 
   const std::uint64_t threshold = max_id_from_rate(*decision.configured_rate);
-  if (knuth_hash(span.trace_id.low) < threshold) {
+  if (knuth_hash(span.trace_id.low) <= threshold) {
     decision.priority = int(SamplingPriority::AUTO_KEEP);
   } else {
     decision.priority = int(SamplingPriority::AUTO_DROP);