Make update_protos test compatible with Windows

The previous variant didn't account for different newline encodings on
Unix and Windows. This wasn't (and still isn't) visible in CI because
the Windows workflow only invokes Cargo tests.

proto/update_protos.py

@@ -78,7 +78,8 @@ def check(proto_packages):
             failed = True
             print("Could not read package %s: %s" % (pkg, e))
             continue
-        if expected == actual:
+        # Ignore differences between newlines on Unix and Windows.
+        if expected.splitlines() == actual.splitlines():
             print("%s OK" % dst)
         else:
             print("%s out of date" % dst)
@@ -94,7 +95,8 @@ def check(proto_packages):
     except OSError as e:
         failed = True
         print("Could not read package lib.rs: %s" % e)
-    if expected == actual:
+    # Ignore differences between newlines on Unix and Windows.
+    if expected.splitlines() == actual.splitlines():
         print("%s OK" % dst)
     else:
         print("%s out of date" % dst)