[APM] Flyout uses full screen

[kpatticha]

Issue

Screen.Recording.2022-11-21.at.23.14.20.mov

Some of the places we use Flyout component

apm • public/components/app/settings/agent_keys/create_agent_key.tsx:
   99    return (
  100:     <EuiFlyout onClose={onCancel} size="s">
  101        <EuiFlyoutHeader hasBorder>

apm • public/components/app/settings/custom_link/create_edit_custom_link_flyout/index.tsx:
  78      <form onSubmit={onSubmit} id="customLink_form">
  79:       <EuiFlyout ownFocus onClose={onClose} size="m">
  80          <EuiFlyoutHeader hasBorder>

apm • public/components/shared/apm_header_action_menu/labs/labs_flyout.tsx:
  85    return (
  86:     <EuiFlyout onClose={onClose}>
  87        <EuiFlyoutHeader hasBorder>

[elasticmachine]

Pinging @elastic/apm-ui (Team:APM)

[kpatticha]

closing it as duplicate of #145814