Remove usage of spaceless tag in Twig templates

Problem/Motivation

spaceless tag has been removed in Twig 3

Proposed resolution

Use spaceless filter instead.
https://twig.symfony.com/doc/3.x/filters/spaceless.html

Before:

{% spaceless %}

{% endspaceless %}

After:

{% apply spaceless %}

{% endapply %}

Remaining tasks

Create a patch.

User interface changes

None.