Fix bug in bump_version.sh

Missing quotes around "version" in module.json
diff --git a/scripts/bump_version.sh b/scripts/bump_version.sh
index 4d08864..97d2f1f 100755
--- a/scripts/bump_version.sh
+++ b/scripts/bump_version.sh
@@ -110,7 +110,7 @@
 mv tmp tests/suites/test_suite_version.data
 
 [ $VERBOSE ] && echo "Bumping version in yotta/data/module.json"
-sed -e "s/\"version\": \".\{1,\}\"/version: \"$VERSION\"/g" < yotta/data/module.json > tmp
+sed -e "s/\"version\": \".\{1,\}\"/\"version\": \"$VERSION\"/g" < yotta/data/module.json > tmp
 mv tmp yotta/data/module.json
 
 [ $VERBOSE ] && echo "Bumping PROJECT_NAME in doxygen/mbedtls.doxyfile and doxygen/input/doc_mainpage.h"