Log is_forward field to dynamo_compile scuba table (#2511)

Summary:

X-link: pytorch/pytorch#138097

^^

Reviewed By: ezyang

Differential Revision: D64438144

userbenchmark/dynamo/dynamobench/_dynamo/utils.py

@@ -774,6 +774,7 @@ def proxy_args_kwargs(args, kwargs):
 
 @dataclasses.dataclass
 class CompilationMetrics:
+    is_forward: bool = dataclasses.field(default=True, init=False)
     compile_id: str
     frame_key: str
     co_name: str
@@ -814,6 +815,7 @@ class CompilationMetrics:
 
 @dataclasses.dataclass
 class BwdCompilationMetrics:
+    is_forward: bool = dataclasses.field(default=False, init=False)
     compile_id: str
     inductor_compile_time_s: Optional[float]
     code_gen_time_s: Optional[float]