Add a Dockerfile and Spec for Fedora 34

linux/packages/fedora34/Dockerfile

@@ -0,0 +1,19 @@
+FROM fedora:34
+
+LABEL maintainer="d.vedenko@audacityteam.org"
+LABEL description="A build environment to check the builds for Fedora package maintainers"
+LABEL version="3.0"
+
+COPY ["dependencies.sh", "/dependencies.sh"]
+RUN ./dependencies.sh
+
+COPY ["entrypoint.sh", "/entrypoint.sh"]
+
+RUN useradd -m user
+#RUN echo "user ALL=(ALL) NOPASSWD: ALL" > /etc/sudoers.d/user
+USER user
+WORKDIR /home/user
+
+COPY ["audacity.spec", "/home/user/audacity.spec"]
+
+ENTRYPOINT ["bash", "-ex", "/entrypoint.sh"]