Add small size to Pajamas alert action buttons

What does this MR do and why?

Vue's GlAlert renders its action buttons at size "small", but the Ruby AlertComponent's actions slot just takes whatever markup a caller passes in, so button size was left up to callers. Most never set it, leaving Ruby-rendered alerts with medium buttons next to small ones in Vue.

Also fixes GitlabUiFormBuilder#submit, which leaked size into button_options as a raw HTML attribute instead of passing it to Pajamas::ButtonComponent.

References

1. GitLab UI Alerts update gitlab-org/gitlab-services/design.gitlab.com!6347 (merged)
2. Integration MR !256040 (closed)
3. Reovate bot MR !257609 (merged)

Screenshots or screen recordings

How to set up and validate locally

1. Toggle alert visibility conditions with temp diff
2. View MR page http://gdk.test:3000/gitlab-org/gitlab-test/-/merge_requests/9

diff --git a/app/views/layouts/header/_openssl_callout.html.haml b/app/views/layouts/header/_openssl_callout.html.haml
index 6d03179a9ec9..50e32bee94d0 100644
--- a/app/views/layouts/header/_openssl_callout.html.haml
+++ b/app/views/layouts/header/_openssl_callout.html.haml
@@ -1,4 +1,4 @@
-- return unless show_openssl_callout?
+-# TEMP force alert: return unless show_openssl_callout?
 
 -# rubocop:disable Gitlab/DocumentationLinks/HardcodedUrl -- This documentation section is only available in version 17.4 onward in GitLab.com.
 - link = link_to('', 'https://docs.gitlab.com/ee/update/versions/gitlab_17_changes.html#1770', target: '_blank', rel: 'noopener noreferrer')
diff --git a/app/views/shared/_service_ping_consent.html.haml b/app/views/shared/_service_ping_consent.html.haml
index 08abbedf0249..1f989b0ff6ba 100644
--- a/app/views/shared/_service_ping_consent.html.haml
+++ b/app/views/shared/_service_ping_consent.html.haml
@@ -1,4 +1,4 @@
-- if session[:ask_for_usage_stats_consent]
+- if true # TEMP force alert: session[:ask_for_usage_stats_consent]
   = render Pajamas::AlertComponent.new(alert_options: { class: 'service-ping-consent-message' }) do |c|
     - c.with_body do
       - docs_link = link_to '', help_page_path('administration/settings/usage_statistics.md'), class: 'gl-link'
scottdejonge@sdejonge--20251209-Q2VMY gitlab % 

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