Fix: Update Prometheus metric label from PromFeature to PromFilter

Changed the Prometheus metric label to better align with the context in which it is being used. This ensures that the metric accurately reflects the specific aspect of the service being monitored.

Signed-off-by: Christian Roessner <c@roessner.co>

server/lualib/filter/filter.go

@@ -475,7 +475,7 @@ func setRequest(r *Request, L *lua.LState) *lua.LTable {
 // It also calls the Lua function with the given parameters and logs the result.
 // The function will return a boolean indicating whether the Lua function was called successfully, and an error if any occurred.
 func executeScriptWithinContext(request *lua.LTable, script *LuaFilter, r *Request, ctx *gin.Context, L *lua.LState) (bool, error) {
-	stopTimer := stats.PrometheusTimer(global.PromFeature, script.Name)
+	stopTimer := stats.PrometheusTimer(global.PromFilter, script.Name)
 
 	defer stopTimer()