PHP 7.4 support

[matusstafura]

Trying to install this to server with php 7.4 (Magento 2.4.1)

Problem 1
- Installation request for dmitrykazak/magento-google-tag-manager 1.1.0 -> satisfiable by dmitrykazak/magento-google-tag-manager[1.1.0].
- dmitrykazak/magento-google-tag-manager 1.1.0 requires php ~7.2.0|~7.3.0 -> your PHP version (7.4.12) does not satisfy that requirement.