Rename MetricSample.sample to MetricSample.value

The datatype of this field is now `MetricValueVariant`, so this commit
tries to rename the field to a more appropriate one.

Signed-off-by: Tiyash Basu <[email protected]>

Author: tiyash-basu-frequenz

RELEASE_NOTES.md

@@ -38,6 +38,8 @@
 
 - Renamed `MetricSampleVariant` to `MetricValueVariant`.
 
+- Rename `MetricSample.sample` to `MetricSample.value`.
+
 ## New Features
 
 - Added a `Frequenz.api.common.v1.types.Decimal` type, compatible with

proto/frequenz/api/common/v1/metrics/metric_sample.proto

@@ -178,7 +178,7 @@ message MetricSample {
   Metric metric = 2;
 
   // The value of the sampled metric.
-  MetricValueVariant sample = 3;
+  MetricValueVariant value = 3;
 
   // List of bounds that apply to the metric sample.
   //

proto/frequenz/api/common/v1/microgrid/components/components.proto

@@ -214,13 +214,13 @@ message ComponentConnection {
 //        {
 //          sampled_at: "2023-10-01T00:00:00Z",
 //          metric: "DC_VOLTAGE_V",
-//          sample: {},
+//          value: {},
 //          bounds: {},
 //        },
 //        {
 //          sampled_at: "2023-10-01T00:00:00Z",
 //          metric: "DC_VOLTAGE_V",
-//          sample: {},
+//          value: {},
 //          bounds: {},
 //        }
 //      ],

proto/frequenz/api/common/v1/microgrid/sensors/sensors.proto

@@ -120,12 +120,12 @@ enum SensorMetric {
 //        {
 //          sampled_at: "2023-10-01T00:00:00Z",
 //          metric: "METRIC_SENSOR_TEMPERATURE",
-//          sample: metric_value_variant: {simple_metric: {value: 23.5},
+//          value: metric_value_variant: {simple_metric: {value: 23.5},
 //        },
 //        {
 //          sampled_at: "2023-10-01T00:00:00Z",
 //          metric: "METRIC_SENSOR_RELATIVE_HUMIDITY",
-//          sample: metric_value_variant: {simple_metric: {value: 23.5},
+//          value: metric_value_variant: {simple_metric: {value: 23.5},
 //        }
 //      ],
 //      states: [