Add /healthcheck probe

Author: Anton Kholodkov

check.http

@@ -0,0 +1 @@
+GET http://localhost:9010/healthcheck

main.py

@@ -15,6 +15,11 @@
 app = FastAPI()
 
 
+@app.get("/healthcheck")
+async def healthcheck():
+    return Response(status_code=200, content="ok", headers={ "Content-Type": "text/plain"})
+
+
 @app.put("/tika/text")
 async def tika(request: Request):