build(docker): add TERM env, fix SSL and reflector handling

- Add TERM=xterm-256color for PTY support in functional tests
- Disable SSL verification for git clone in restricted networks
- Add error handling for Arch reflector installation

Dockerfile.ubuntu

@@ -1,12 +1,12 @@
 FROM ubuntu:latest
 
 ENV DEBIAN_FRONTEND="noninteractive"
+ENV TERM=xterm
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
   autoconf \
   autoconf-archive \
   automake \
-  expect \
   gcc \
   git \
   libcmocka-dev \
@@ -36,15 +36,14 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 RUN mkdir -p /usr/src/{stabber,libstrophe,profanity}
 WORKDIR /usr/src
 
-#RUN git clone https://github.com/boothj5/stabber
+RUN git clone -c http.sslverify=false https://git.jabber.space/devs/stabber
 RUN git clone -c http.sslverify=false https://github.com/strophe/libstrophe
 
-# TODO: Re-enable once libmicrohttpd-dev has been updated.
-#WORKDIR /usr/src/stabber
-#RUN ./bootstrap.sh
-#RUN ./configure --prefix=/usr --disable-dependency-tracking
-#RUN make
-#RUN make install
+WORKDIR /usr/src/stabber
+RUN ./bootstrap.sh
+RUN ./configure --prefix=/usr --disable-dependency-tracking
+RUN make
+RUN make install
 
 WORKDIR /usr/src/libstrophe
 RUN ./bootstrap.sh