[chore] Add stability level for metrics (open-telemetry#43870)

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Ex. Adding a feature - Explain what this achieves.-->
#### Description

Follow-up from
open-telemetry#42809
to fix failing tests of
open-telemetry/opentelemetry-collector#14070.

Signed-off-by: ChrsMark <[email protected]>

Author: ChrsMark

receiver/ciscoosreceiver/internal/scraper/systemscraper/documentation.md

@@ -16,25 +16,25 @@ metrics:
 
 Device availability (1 = up, 0 = down)
 
-| Unit | Metric Type | Value Type |
-| ---- | ----------- | ---------- |
-| 1 | Gauge | Int |
+| Unit | Metric Type | Value Type | Stability |
+| ---- | ----------- | ---------- | --------- |
+| 1 | Gauge | Int | development |
 
 ### system.cpu.utilization
 
 Percentage of CPU time in use.
 
-| Unit | Metric Type | Value Type |
-| ---- | ----------- | ---------- |
-| 1 | Gauge | Double |
+| Unit | Metric Type | Value Type | Stability |
+| ---- | ----------- | ---------- | --------- |
+| 1 | Gauge | Double | development |
 
 ### system.memory.utilization
 
 Percentage of memory bytes in use.
 
-| Unit | Metric Type | Value Type |
-| ---- | ----------- | ---------- |
-| 1 | Gauge | Double |
+| Unit | Metric Type | Value Type | Stability |
+| ---- | ----------- | ---------- | --------- |
+| 1 | Gauge | Double | development |
 
 ## Resource Attributes
 

receiver/ciscoosreceiver/internal/scraper/systemscraper/metadata.yaml

@@ -18,20 +18,26 @@ metrics:
   cisco.device.up:
     enabled: true
     description: Device availability (1 = up, 0 = down)
+    stability:
+      level: development
     unit: "1"
     gauge:
       value_type: int
 
   system.cpu.utilization:
     enabled: true
     description: Percentage of CPU time in use.
+    stability:
+      level: development
     unit: "1"
     gauge:
       value_type: double
 
   system.memory.utilization:
     enabled: true
     description: Percentage of memory bytes in use.
+    stability:
+      level: development
     unit: "1"
     gauge:
       value_type: double