scripts: update open calls to use explicit encoding

BUG=b:187789896
TEST=`cros lint` is clean here

Change-Id: Ia54475869c17292505537334362cd4cff6438b14
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/4290041
Commit-Queue: Cindy Lin <xcl@google.com>
Reviewed-by: Cindy Lin <xcl@google.com>
Tested-by: Mike Frysinger <vapier@chromium.org>
Auto-Submit: Mike Frysinger <vapier@chromium.org>
diff --git a/scripts/cros_deps_diff.py b/scripts/cros_deps_diff.py
index 32345bb..855a9af 100644
--- a/scripts/cros_deps_diff.py
+++ b/scripts/cros_deps_diff.py
@@ -163,8 +163,8 @@
 
     input_deps = []
     for i in options.inputs:
-        with open(i) as handle:
-            input_deps.append(json.loads(handle.read()))
+        with open(i, "rb") as handle:
+            input_deps.append(json.load(handle))
 
     version_map = GetVersionMap(input_deps)
     divergent_set = GetDivergentSet(version_map, len(input_deps))