Shift stringslint to using python3.

Bug: 169704254
Test: manual
Change-Id: I175bdf75e7424bef6d4ac9f51797510766de2b14
(cherry picked from commit 85ccd0418097d774d8db8af77da2d6b5ed75d743)
Merged-In: I354ef4b12c75505a069fdf657ab98a9b122785c7
diff --git a/tools/stringslint/stringslint_sha.sh b/tools/stringslint/stringslint_sha.sh
index bd80bb4..bd05698 100755
--- a/tools/stringslint/stringslint_sha.sh
+++ b/tools/stringslint/stringslint_sha.sh
@@ -1,5 +1,5 @@
 #!/bin/bash
 LOCAL_DIR="$( dirname ${BASH_SOURCE} )"
 git show --name-only --pretty=format: $1 | grep values/strings.xml | while read file; do
-    python $LOCAL_DIR/stringslint.py <(git show $1:$file) <(git show $1^:$file)
+    python3 $LOCAL_DIR/stringslint.py <(git show $1:$file) <(git show $1^:$file)
 done