proxy: fix typo

(cherry picked from commit 13f4c143)

src/opnsense/mvc/app/controllers/OPNsense/Proxy/forms/main.xml

@@ -117,7 +117,7 @@
                 <label>Enable local cache (requires service restart)</label>
                 <type>checkbox</type>
                 <help><![CDATA[Enable or disable the local cache.<br/>
-        Curently only ufs directory cache type is supported.<br/>
+        Currently only ufs directory cache type is supported.<br/>
         <b class="text-danger">Do not enable on embedded systems with SD or CF cards as this may break your drive.</b>]]></help>
             </field>
             <field>