[improve] create disclaimer file, add incubating in describe (#1764)

Signed-off-by: tomsun28 <tomsun28@outlook.com>

.asf.yaml

@@ -16,7 +16,7 @@
 #
 
 github:
-  description: Apache HertzBeat is a real-time monitoring system with agentless, performance cluster, prometheus-compatible, custom monitoring and status page building capabilities.
+  description: Apache HertzBeat(incubating) is a real-time monitoring system with agentless, performance cluster, prometheus-compatible, custom monitoring and status page building capabilities.
   homepage: https://hertzbeat.apache.org/
   labels:
     - monitoring

.licenserc.yaml

@@ -48,6 +48,7 @@ header:
     - 'material/**'
     - 'LICENSE'
     - 'NOTICE'
+    - 'DISCLAIMER'
     - '**/LICENSE'
     - '**/NOTICE'
     - '.all-contributorsrc'

DISCLAIMER

@@ -0,0 +1,10 @@
+Apache HertzBeat (incubating) is an effort undergoing incubation at the Apache 
+Software Foundation (ASF), sponsored by the Apache Incubator PMC.
+
+Incubation is required of all newly accepted projects until a further review
+indicates that the infrastructure, communications, and decision making process
+have stabilized in a manner consistent with other successful ASF projects.
+
+While incubation status is not necessarily a reflection of the completeness
+or stability of the code, it does indicate that the project has yet to be
+fully endorsed by the ASF.