Fix deprecation warnings when running tests

[andysellick]

What / why

Running the tests for the gem locally some deprecation warnings were being thrown up. They were:

• action_view.raise_on_missing_translations is deprecated
• rendering a template with a . in it is deprecated

The first one was an easy fix, just swapping out the old for the new. The second one was a little more complicated. The attachment component has several partials that are .svg files but are rendered like partials. I renamed these files to .html.erb and removed the file extension from the render call, which removed the deprecation warning but suddenly caused one of the component audit tests to fail.

This was because the formerly .svg files were now being recognised by the auditor as potential components that should be included when suggesting Sass/JS for applications, even though they were in a subdirectory for partials and not the main directory location for component templates. The fix for this was to amend the regex that matches this to remove the / character when matching components. So if this was a template...

<%= render "govuk_publishing_components/components/component" %>
<%= render "govuk_publishing_components/components/partials/partial" %>

Previously the auditor was identifying both lines as components, when only the first line is a true component. The question I'm left with is why the regex originally included the / character when matching... it seems a bit odd. I've checked it locally with collections and it seems to still produce the right suggested Sass/JS output, but perhaps some more thorough checking would be useful.

I think this only really happened with components within components but I think one of the publishing apps might pull in a partial from the header component directly for some reason, I'm hoping someone can shed some light on this.

The specific deprecation warnings were:

DEPRECATION WARNING: action_view.raise_on_missing_translations is deprecated and will be removed in Rails 6.2. 
Set i18n.raise_on_missing_translations instead. Note that this new setting also affects how missing translations are handled in controllers. 
(called from block (2 levels) in <top (required)> at /Users/andysellick/workspace/govuk/govuk_publishing_components/spec/component_guide/component_audit_spec.rb:5)

DEPRECATION WARNING: Rendering actions with '.' in the name is deprecated: 
govuk_publishing_components/components/attachment/_thumbnail_spreadsheet.svg 
(called from _app_views_layouts_application_html_erb__3522064166250592246_71200 at /Users/andysellick/workspace/govuk/govuk_publishing_components/spec/dummy/app/views/layouts/application.html.erb:16)

DEPRECATION WARNING: Rendering actions with '.' in the name is deprecated: 
govuk_publishing_components/components/attachment/_thumbnail_spreadsheet.svg 
(called from _app_views_layouts_application_html_erb__3522064166250592246_71200 at /Users/andysellick/workspace/govuk/govuk_publishing_components/spec/dummy/app/views/layouts/application.html.erb:16)

DEPRECATION WARNING: Rendering actions with '.' in the name is deprecated: 
govuk_publishing_components/components/attachment/_thumbnail_generic.svg 
(called from block (3 levels) in ___sers_andysellick_workspace_govuk_govuk_publishing_components_app_views_govuk_publishing_components_components__attachment_html_erb___2448659267357681147_74020 at /Users/andysellick/workspace/govuk/govuk_publishing_components/app/views/govuk_publishing_components/components/_attachment.html.erb:48)

DEPRECATION WARNING: Rendering actions with '.' in the name is deprecated: 
govuk_publishing_components/components/attachment/_thumbnail_generic.svg 
(called from block (3 levels) in ___sers_andysellick_workspace_govuk_govuk_publishing_components_app_views_govuk_publishing_components_components__attachment_html_erb___2448659267357681147_74020 at /Users/andysellick/workspace/govuk/govuk_publishing_components/app/views/govuk_publishing_components/components/_attachment.html.erb:48)

DEPRECATION WARNING: Rendering actions with '.' in the name is deprecated: 
govuk_publishing_components/components/attachment/_thumbnail_document.svg 
(called from block (3 levels) in ___sers_andysellick_workspace_govuk_govuk_publishing_components_app_views_govuk_publishing_components_components__attachment_html_erb___2448659267357681147_74020 at /Users/andysellick/workspace/govuk/govuk_publishing_components/app/views/govuk_publishing_components/components/_attachment.html.erb:44)

DEPRECATION WARNING: Rendering actions with '.' in the name is deprecated: 
govuk_publishing_components/components/attachment/_thumbnail_document.svg 
(called from block (3 levels) in ___sers_andysellick_workspace_govuk_govuk_publishing_components_app_views_govuk_publishing_components_components__attachment_html_erb___2448659267357681147_74020 at /Users/andysellick/workspace/govuk/govuk_publishing_components/app/views/govuk_publishing_components/components/_attachment.html.erb:44)

DEPRECATION WARNING: Rendering actions with '.' in the name is deprecated: 
govuk_publishing_components/components/attachment/_thumbnail_spreadsheet.svg 
(called from block (3 levels) in ___sers_andysellick_workspace_govuk_govuk_publishing_components_app_views_govuk_publishing_components_components__attachment_html_erb___2448659267357681147_74020 at /Users/andysellick/workspace/govuk/govuk_publishing_components/app/views/govuk_publishing_components/components/_attachment.html.erb:46)

DEPRECATION WARNING: Rendering actions with '.' in the name is deprecated: 
govuk_publishing_components/components/attachment/_thumbnail_spreadsheet.svg 
(called from block (3 levels) in ___sers_andysellick_workspace_govuk_govuk_publishing_components_app_views_govuk_publishing_components_components__attachment_html_erb___2448659267357681147_74020 at /Users/andysellick/workspace/govuk/govuk_publishing_components/app/views/govuk_publishing_components/components/_attachment.html.erb:46)

Visual Changes

None.