MarshalText implementation, cleanup

Makefile

@@ -192,7 +192,7 @@ test-coverage: | $(GOCOVMERGE)
 	done; \
 	$(GOCOVMERGE) $$(find . -name coverage.out) > coverage.txt
 
-# Adding a directory will include all benchmarks in that directory if a filter is not specified.
+# Adding a directory will include all benchmarks in that direcotry if a filter is not specified.
 BENCHMARK_TARGETS := sdk/trace
 .PHONY: benchmark
 benchmark: $(BENCHMARK_TARGETS:%=benchmark/%)

sdk/metric/metricdata/data.go

@@ -16,7 +16,6 @@ package metricdata // import "go.opentelemetry.io/otel/sdk/metric/metricdata"
 
 import (
 	"encoding/json"
-	"fmt"
 	"time"
 
 	"go.opentelemetry.io/otel/attribute"
@@ -213,12 +212,17 @@ type Extrema[N int64 | float64] struct {
 	valid bool
 }
 
-// MarshalJson converts the Extrema value to JSON number
-func (e *Extrema[N]) MarshalJSON() ([]byte, error) {
+// MarshalText converts the Extrema value to text.
+func (e Extrema[N]) MarshalText() ([]byte, error) {
 	if !e.valid {
 		return []byte("0"), nil
 	}
-	return []byte(json.Number(fmt.Sprint(e.value))), nil
+	return json.Marshal(e.value)
+}
+
+// MarshalJSON converts the Extrema value to JSON number.
+func (e *Extrema[N]) MarshalJSON() ([]byte, error) {
+	return e.MarshalText()
 }
 
 // NewExtrema returns an Extrema set to v.