Attempt fixing the builds with new Docker images

Diffs=
8f8e06b9e Attempt fixing the builds with new Docker images (#5253)
diff --git a/.rive_head b/.rive_head
index 065650d..38bffa2 100644
--- a/.rive_head
+++ b/.rive_head
@@ -1 +1 @@
-7768798a7efb34fcbf94e76a348af064d28298f7
+8f8e06b9e56bc373e55a7f9b940d0457fe119200
diff --git a/Dockerfile b/Dockerfile
index 5a6ac7c..31ab937 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,6 +1,8 @@
 FROM dart:stable
 
 RUN apt update && apt-get -y install unzip zip clang cmake ninja-build pkg-config libgtk-3-dev xvfb cargo wget g++
+
+WORKDIR /
 RUN wget https://github.com/premake/premake-core/releases/download/v5.0.0-alpha15/premake-5.0.0-alpha15-linux.tar.gz
 RUN tar -xvf premake-5.0.0-alpha15-linux.tar.gz
 RUN mv premake5 /usr/bin/