Invalid paths are not correctly handled

Problem/Motivation

When navigating to an invalid path, this module does not catch the resulting Exception from getting the alias.
See the related issues where this bug was (possibly) introduced: https://www.drupal.org/node/2810961 →

Steps to reproduce

Have a setup where this module will be active
Navigate to https://yoursite.com/index.phpsometext

Proposed resolution

Catch the Exception, return NULL and catch the NULL further down the line.

Remaining tasks

Review and apply patch.

User interface changes

None

API changes

None

Data model changes

Small change in the return function for createUrlFromRelativeUri()