fix: Move content into to frontend directory

Doing this BEFORE the merge prevents a lot of merge conflicts.

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

frontend/src/components/login-page/auth/via-one-click.tsx

@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import React, { useMemo } from 'react'
+import { SocialLinkButton } from './social-link-button/social-link-button'
+import type { AuthProvider, AuthProviderWithCustomName } from '../../../api/config/types'
+import { getOneClickProviderMetadata } from './utils/get-one-click-provider-metadata'
+
+export interface ViaOneClickProps {
+  provider: AuthProvider
+}
+
+/**
+ * Renders a login button for the given one-click login provider.
+ *
+ * @param provider The one-click login provider. In case of ones that can be defined multiple times, an identifier and a label is required.
+ */
+export const ViaOneClick: React.FC<ViaOneClickProps> = ({ provider }) => {
+  const { className, icon, url, name } = useMemo(() => getOneClickProviderMetadata(provider), [provider])
+  const text = (provider as AuthProviderWithCustomName).providerName || name
+
+  return (
+    <SocialLinkButton backgroundClass={className} icon={icon} href={url} title={text}>
+      {text}
+    </SocialLinkButton>
+  )
+}