Explicitly cast int to string when expected by PHP functions
Summary: Avoid `Parameter $foo of function bar expects string, int[|string] given` output in static code analysis by explicitly casting to string when a return value is an int, or by passing a string by encapsulating an int with apostrophes.
Test Plan: Run static code analysis.
Reviewers: O1 Blessed Committers, valerio.bozzolan
Reviewed By: O1 Blessed Committers, valerio.bozzolan
Subscribers: tobiaswiese, valerio.bozzolan, Matthew, Cigaryno
Differential Revision: https://we.phorge.it/D26074