Revert "fix: convert datetime back to proto for unit tests (#511)"

This reverts commit e1c787d.

gapic/ads-templates/tests/unit/gapic/%name_%version/%sub/test_%service.py.j2

@@ -7,7 +7,6 @@ from unittest import mock
 import grpc
 import math
 import pytest
-from proto.marshal.rules.dates import DurationRule, TimestampRule
 
 {# Import the service itself as well as every proto module that it imports. -#}
 {% filter sort_lines -%}
@@ -376,13 +375,7 @@ def test_{{ method.name|snake_case }}_flattened():
  assert len(call.mock_calls) == 1
  _, args, _ = call.mock_calls[0]
  {% for key, field in method.flattened_fields.items() -%}{%- if not field.oneof or field.proto3_optional %}
- {% if field.ident|string() == 'timestamp.Timestamp' -%}
- assert TimestampRule().to_proto(args[0].{{ key }}) == {{ field.mock_value }}
- {% elif field.ident|string() == 'duration.Duration' -%}
- assert DurationRule().to_proto(args[0].{{ key }}) == {{ field.mock_value }}
- {% else -%}
  assert args[0].{{ key }} == {{ field.mock_value }}
- {% endif %}
  {% endif %}{% endfor %}
  {%- for oneofs in method.flattened_oneof_fields().values() %}
  {%- with field = oneofs[-1] %}

gapic/templates/tests/unit/gapic/%name_%version/%sub/test_%service.py.j2

@@ -8,7 +8,6 @@ import grpc
 from grpc.experimental import aio
 import math
 import pytest
-from proto.marshal.rules.dates import DurationRule, TimestampRule
 
 {# Import the service itself as well as every proto module that it imports. -#}
 {% filter sort_lines -%}
@@ -575,13 +574,7 @@ def test_{{ method.name|snake_case }}_flattened():
  assert len(call.mock_calls) == 1
  _, args, _ = call.mock_calls[0]
  {% for key, field in method.flattened_fields.items() -%}{%- if not field.oneof or field.proto3_optional %}
- {% if field.ident|string() == 'timestamp.Timestamp' -%}
- assert TimestampRule().to_proto(args[0].{{ key }}) == {{ field.mock_value }}
- {% elif field.ident|string() == 'duration.Duration' -%}
- assert DurationRule().to_proto(args[0].{{ key }}) == {{ field.mock_value }}
- {% else -%}
  assert args[0].{{ key }} == {{ field.mock_value }}
- {% endif %}
  {% endif %}{% endfor %}
  {%- for oneofs in method.flattened_oneof_fields().values() %}
  {%- with field = oneofs[-1] %}
@@ -660,13 +653,7 @@ async def test_{{ method.name|snake_case }}_flattened_async():
  assert len(call.mock_calls)
  _, args, _ = call.mock_calls[0]
  {% for key, field in method.flattened_fields.items() -%}{%- if not field.oneof or field.proto3_optional %}
- {% if field.ident|string() == 'timestamp.Timestamp' -%}
- assert TimestampRule().to_proto(args[0].{{ key }}) == {{ field.mock_value }}
- {% elif field.ident|string() == 'duration.Duration' -%}
- assert DurationRule().to_proto(args[0].{{ key }}) == {{ field.mock_value }}
- {% else -%}
  assert args[0].{{ key }} == {{ field.mock_value }}
- {% endif %}
  {% endif %}{% endfor %}
  {%- for oneofs in method.flattened_oneof_fields().values() %}
  {%- with field = oneofs[-1] %}