Add a script that fixes style related things (#3234)

* Add a script that fixes style related things

It is kind of tedious that we need make sure that every style check
passes with any change we make. A script is added, which does all the
things for us so that we dont have to run separate commands.

* run fix style string in reindent target

Makefile

@@ -34,7 +34,7 @@ clean: clean-extension
 
 # apply or check style
 reindent:
-	cd ${citus_abs_top_srcdir} && citus_indent --quiet
+	${citus_abs_top_srcdir}/ci/fix_style.sh
 check-style:
 	cd ${citus_abs_top_srcdir} && citus_indent --quiet --check
 .PHONY: reindent check-style

ci/fix_style.sh

@@ -0,0 +1,14 @@
+#!/bin/sh
+
+# fail if trying to reference a variable that is not set.
+set -u / set -o nounset
+# exit immediately if a command fails
+set -e
+
+cidir="${0%/*}"
+cd ${cidir}/..
+
+ci/editorconfig.sh
+ci/remove_useless_declarations.sh
+
+citus_indent . --quiet