TT#15855 Fix shellcheck warnings for repo to mark it as clean

In last_file line 6:
    sort -n | tail -1 | cut -f1 -d'.'\
                                     ^-- SC2026: This word is outside of quotes. Did you intend to 'nest '"'single quotes'"' instead'?

Change-Id: I638b69416d1210b039996bcefb060f2d61f646c4

last_file

@@ -3,6 +3,6 @@
 LAST=$(\
     find db_scripts/ -name "*.up" |\
     awk -vFS=/ -vOFS=/ '{ print $NF }' |\
-    sort -n | tail -1 | cut -f1 -d'.'\
+    sort -n | tail -1 | cut -f1 -d'.' \
 );
 find . -type f -name "$LAST.up"

next_id

@@ -3,6 +3,6 @@
 LAST=$(\
     find db_scripts/ -name "*.up" |\
     awk -vFS=/ -vOFS=/ '{ print $NF }' |\
-    sort -n | tail -1 | cut -f1 -d'.'\
+    sort -n | tail -1 | cut -f1 -d'.' \
 );
 echo $(( LAST + 1))