Apply update_copyright_headers.sh to staged files as well

update_copyright_headers.sh

@@ -10,6 +10,12 @@
 current_year=$(date +'%Y')
 echo Updating copyright headers in Java, Kotlin, and Groovy source code for year $current_year
 
+# Added/Modified this year and committed
 for file in $(git --no-pager diff --name-only --diff-filter=AM @{$current_year-01-01}..@{$current_year-12-31} | egrep "^.+\.(java|kotlin|groovy)$" | uniq); do
 	sed -i '' -E "s/Copyright 2002-[0-9]{4}/Copyright 2002-$current_year/g" $file;
 done
+
+# Added/Modified and staged but not yet committed
+for file in $(git --no-pager diff --name-only --diff-filter=AM --cached | egrep "^.+\.(java|kotlin|groovy)$" | uniq); do
+	sed -i '' -E "s/Copyright 2002-[0-9]{4}/Copyright 2002-$current_year/g" $file;
+done