Update mautrix-python and alpine

Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.14
+FROM alpine:3.15
 
 ARG TARGETARCH=amd64
 

mautrix_signal/__main__.py

@@ -41,7 +41,6 @@ class SignalBridge(Bridge):
     command = "python -m mautrix-signal"
     description = "A Matrix-Signal puppeting bridge."
     repo_url = "https://github.com/mautrix/signal"
-    real_user_content_key = "net.maunium.signal.puppet"
     version = version
     markdown_version = linkified_version
     config_class = Config

requirements.txt

@@ -4,5 +4,5 @@ commonmark>=0.8,<0.10
 aiohttp>=3,<4
 yarl>=1,<2
 attrs>=19.1
-mautrix>=0.13.1,<0.14
+mautrix>=0.13.3,<0.14
 asyncpg>=0.20,<0.26