Fixes & improvements 🛠

We've been spending some time fixing various issues. Here's a list of the most relevant: * Fixed an issue where adding a new line to product's fixed start times was causing an error * Fixed an issue where invalid characters in product image file names where breaking the images. Not nice. Additionally, these fixes should help with search-engine visbility. * Fixed some falsy redirection links within Rentle Admin * When the Branding block was not installed, there was a double "Branding" title in Account > General settings, but not anymore. * Fixed issue of some customers getting duplicate Google Tag Manager events. GTM also now receives commerce events even when Google Analytics isn't connected