NewProvisioningSession expects pkcs8 private key and SHA race fix

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Fix SHA hashing to remove race condition. This change
fixes the implementation by passing in the digest buffer.

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The input to ProvisioningEngine::NewProvisioningSession should be
pkcs8 private key instead of pkcs1 private key

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=151273394

Change-Id: Ibcdff7757b2ac2878ee8b1b88365083964bfa10a

provisioning_sdk/public/python/BUILD

@@ -18,8 +18,13 @@ filegroup(
 
 py_library(
     name = "test_data_utility",
-    srcs = ["test_data_utility.py"],
-    data = ["//example:example_data"],
+    srcs = [
+        "test_data_provider.py",
+        "test_data_utility.py",
+    ],
+    data = [
+        "//example:example_data",
+    ],
     deps = [
         "//protos/public:certificate_provisioning_py_pb2",
     ],