Fix json formatting

Change-Id: Ib3532091aa6405e9c0bed864aa85d2fc73a21809
Reviewed-on: https://pigweed-review.googlesource.com/c/open-dice/+/172791
Pigweed-Auto-Submit: Darren Krahn <dkrahn@google.com>
Commit-Queue: Auto-Submit <auto-submit@pigweed-service-accounts.iam.gserviceaccount.com>
Reviewed-by: Rob Mohr <mohrr@google.com>

pigweed.json

diff --git a/pigweed.json b/pigweed.json
index 949ffa8..e5184f5 100644
--- a/pigweed.json
+++ b/pigweed.json
@@ -11,10 +11,10 @@
     "pw_presubmit": {
       "format": {
         "python_formatter": "black",
-	"exclude": [
-	  "third_party/.*/src",
-	  "third_party/boringssl/err_data.c"
-	]
+        "exclude": [
+          "third_party/.*/src",
+          "third_party/boringssl/err_data.c"
+        ]
       }
     },
     "pw_env_setup": {