setup.py: remove dependency elasticsearch-curator

* It's not needed anymore.
* Remove upper limit for black that was there to avoid conflicts with
  elasticsearch-curator.

Bug: T345337
Bug: T361647
Change-Id: I633b8c62a3145a0ddbf0e53bd281c7135cb5b119

setup.py

@@ -11,7 +11,6 @@
     "cumin>=3.0.2",
     "dnspython~=2.0.0",
     "elasticsearch>=5.0.0,<7.15.0",
-    "elasticsearch-curator~=5.0",
     "gitpython>=3.1.14",
     "kafka-python>=2.0.1",
     "kubernetes==12.0.*",  # frozen to the version available on debian bullseye
@@ -49,7 +48,7 @@
         "types-setuptools",
     ],
     "format": [
-        "black<=21.12b0",  # this is needed so that it doesn't confict with curator
+        "black",
         "isort",
     ],
     "prospector": [