Add hostea as a gold sponsor (#109)

![image](https://gitea.com/gitea/theme/attachments/db487247-b0d2-4af1-b279-4cc83f27a6c2)

Co-authored-by: Loïc Dachary <loic@dachary.org>
Reviewed-on: https://gitea.com/gitea/theme/pulls/109
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-by: 6543 <6543@obermui.de>
Co-authored-by: dachary <dachary@noreply.gitea.io>
Co-committed-by: dachary <dachary@noreply.gitea.io>

layouts/home/index.html

@@ -66,6 +66,9 @@
 				<div class="column">
 					<a href="https://opencollective.com/gitea"><img src="/images/opencollective.svg" style="height:100px" alt="Open Collective"></a>
 				</div>
+				<div class="column">
+					<a href="https://hostea.org/blog/"><img src="/images/hostea.png" style="height:100px" alt="Hostea"></a>
+				</div>
 			</div>
 		</div>
 	</div>