Corrects return type and updates example code

Co-Authored-By: CalledLuca <58666938+CalledLuca@users.noreply.github.com>

Author: Laky-64

PyTgCalls/Client.xml

@@ -35,13 +35,13 @@
             <category>
                 <pg-title>STATIC METHODS</pg-title>
                 <subtext>
-                    <category-title><shi>async</shi> <ref><sb>calls</sb></ref> <shi>-> dict</shi>[<shi>str</shi>, <docs-ref link="/PyTgCalls/Advanced Types/Call">Call</docs-ref>]</category-title>
+                    <category-title><shi>async</shi> <ref><sb>calls</sb></ref> <shi>-> dict</shi>[<shi>int</shi>, <docs-ref link="/PyTgCalls/Advanced Types/Call">Call</docs-ref>]</category-title>
                     <config id="LIST_CALLS_DESC"/>
 
-                    <category-title><shi>async</shi> <ref><sb>group_calls</sb></ref> <shi>-> dict</shi>[<shi>str</shi>, <docs-ref link="/PyTgCalls/Advanced Types/Call">Call</docs-ref>]</category-title>
+                    <category-title><shi>async</shi> <ref><sb>group_calls</sb></ref> <shi>-> dict</shi>[<shi>int</shi>, <docs-ref link="/PyTgCalls/Advanced Types/Call">Call</docs-ref>]</category-title>
                     <subtext><text>Get all group calls</text></subtext>
 
-                    <category-title><shi>async</shi> <ref><sb>private_calls</sb></ref> <shi>-> dict</shi>[<shi>str</shi>, <docs-ref link="/PyTgCalls/Advanced Types/Call">Call</docs-ref>]</category-title>
+                    <category-title><shi>async</shi> <ref><sb>private_calls</sb></ref> <shi>-> dict</shi>[<shi>int</shi>, <docs-ref link="/PyTgCalls/Advanced Types/Call">Call</docs-ref>]</category-title>
                     <subtext><text>Get all private calls</text></subtext>
 
                     <category-title><ref><sb>cache_peer</sb></ref> <shi>-></shi> <config id="ARG_UNION_PEER"/></category-title>

PyTgCalls/Using Filters.xml

@@ -19,7 +19,7 @@
                     from pytgcalls import filters
                     from pytgcalls.types import ChatUpdate
                     ...
-                    @pytgcalls.on_update(filters.chat_update(ChatUpdate.Status.INCOMING_CALL))
+                    @app.on_update(filters.chat_update(ChatUpdate.Status.INCOMING_CALL))
                     def on_incoming_call(client, update):
                         print("Incoming call!", update)
                 </syntax-highlight>
@@ -61,7 +61,7 @@
                         from pytgcalls import filters
                         from pytgcalls.types import ChatUpdate
                         ...
-                        @pytgcalls.on_update(~filters.chat_update(ChatUpdate.Status.LEFT_GROUP) &amp; filters.chat(1234567890))
+                        @app.on_update(~filters.chat_update(ChatUpdate.Status.LEFT_GROUP) &amp; filters.chat(1234567890))
                         def on_incoming_voice_call(client, update):
                             print("Left chat!", update)
                     </syntax-highlight>
@@ -74,7 +74,7 @@
                         from pytgcalls import filters
                         from pytgcalls.types import ChatUpdate
                         ...
-                        @pytgcalls.on_update(filters.chat(1234567890) &amp; (filters.chat_update(ChatUpdate.Status.LEFT_GROUP) | filters.chat_update(ChatUpdate.Status.INCOMING_CALL)))
+                        @app.on_update(filters.chat(1234567890) &amp; (filters.chat_update(ChatUpdate.Status.LEFT_GROUP) | filters.chat_update(ChatUpdate.Status.INCOMING_CALL)))
                         def on_incoming_voice_call(client, update):
                             print("Incoming voice call or left chat!", update)
                     </syntax-highlight>