Remove system.swap.* metrics if /proc/vmstat is not available

Author: dabico

instrumentation/opentelemetry-instrumentation-system-metrics/src/opentelemetry/instrumentation/system_metrics/__init__.py

@@ -153,6 +153,13 @@
     # see https://github.com/giampaolo/psutil/issues/1219
     _DEFAULT_CONFIG.pop("system.network.connections")
 
+if psutil.LINUX:
+    # see https://github.com/open-telemetry/opentelemetry-python-contrib/issues/3740
+    vmstat = os.path.join(psutil.PROCFS_PATH, "vmstat")
+    if not os.path.exists(vmstat):
+        _DEFAULT_CONFIG.pop("system.swap.usage")
+        _DEFAULT_CONFIG.pop("system.swap.utilization")
+
 
 class SystemMetricsInstrumentor(BaseInstrumentor):
     def __init__(