Remove hard-coded percentiles from MicrometerMetricsTracker

Rather than hard-coding a client-side calculated percentile in HikariCP's code, it is best to leave these configuration decisions to HikariCP users in their code. Users can configure percentiles and whether to record a histogram for HikariCP metrics via a `MeterFilter`.

Resolves micrometer-metrics/micrometer#91

src/main/java/com/zaxxer/hikari/metrics/micrometer/MicrometerMetricsTracker.java

@@ -39,19 +39,16 @@ public class MicrometerMetricsTracker implements IMetricsTracker
    {
       this.connectionObtainTimer = Timer.builder(METRIC_NAME_WAIT)
          .description("Connection acquire time")
-         .publishPercentiles(0.95)
          .tags(METRIC_CATEGORY, poolName)
          .register(meterRegistry);
 
       this.connectionCreation = Timer.builder(METRIC_NAME_CONNECT)
          .description("Connection creation time")
-         .publishPercentiles(0.95)
          .tags(METRIC_CATEGORY, poolName)
          .register(meterRegistry);
 
       this.connectionUsage = Timer.builder(METRIC_NAME_USAGE)
          .description("Connection usage time")
-         .publishPercentiles(0.95)
          .tags(METRIC_CATEGORY, poolName)
          .register(meterRegistry);