fix: move gRPC dependencies to an extra

PR #3687 added a spiffy feature to ingest streaming features, but this
came along with a large batch of depdencies.  Notable this induces a
core dependency on `protobuf>=4.21.6` while Feast itself is on
`protobuf<4.23.4,>3.20`.  This is a fiddly narrow range and excludes
all 3.x uses.

Signed-off-by: Chris Burroughs <chris.burroughs@gmail.com>

setup.py

@@ -45,10 +45,6 @@
     "colorama>=0.3.9,<1",
     "dill~=0.3.0",
     "fastavro>=1.1.0,<2",
-    "grpcio>=1.56.2,<2",
-    "grpcio-tools>=1.56.2,<2",
-    "grpcio-reflection>=1.56.2,<2",
-    "grpcio-health-checking>=1.56.2,<2",
     "mypy-protobuf==3.1",
     "Jinja2>=2,<4",
     "jsonschema",
@@ -146,7 +142,14 @@
 
 IBIS_REQUIRED = [
     "ibis-framework",
-    "ibis-substrait"
+    "ibis-substrait",
+]    
+
+GRPCIO_REQUIRED = [
+    "grpcio>=1.56.2,<2",
+    "grpcio-tools>=1.56.2,<2",
+    "grpcio-reflection>=1.56.2,<2",
+    "grpcio-health-checking>=1.56.2,<2",
 ]
 
 CI_REQUIRED = (
@@ -207,6 +210,7 @@
     + ROCKSET_REQUIRED
     + HAZELCAST_REQUIRED
     + IBIS_REQUIRED
+    + GRPCIO_REQUIRED
 )
 
 
@@ -373,6 +377,7 @@ def run(self):
         "docs": DOCS_REQUIRED,
         "cassandra": CASSANDRA_REQUIRED,
         "hazelcast": HAZELCAST_REQUIRED,
+        "grpcio": GRPCIO_REQUIRED,
         "rockset": ROCKSET_REQUIRED,
         "ibis": IBIS_REQUIRED
     },