Removed default terraform configuration

Atlantis server requires a default tf version, however, this setting
here also has the side effect to have a default version in utopia
terraform. This is not safe, as you might updating the tf state version
by mistake.

Move this setting to the atlantis runtime config, so we check and
run only the relevant terraform version in case of manual intervention

Dockerfile

@@ -27,13 +27,9 @@ FROM ${ATLANTIS_BASE}:${ATLANTIS_BASE_TAG_DATE}-${ATLANTIS_BASE_TAG_TYPE} AS bas
 # Get the architecture the image is being built for
 ARG TARGETPLATFORM
 
-# install terraform binaries
-# renovate: datasource=github-releases depName=hashicorp/terraform versioning=hashicorp
-ENV DEFAULT_TERRAFORM_VERSION=1.4.6
-
 # In the official Atlantis image we only have the latest of each Terraform version.
 SHELL ["/bin/bash", "-o", "pipefail", "-c"]
-RUN AVAILABLE_TERRAFORM_VERSIONS="0.11.15 0.12.31 0.13.7 0.14.9 0.15.5 1.0.10 1.1.9 1.2.9 1.3.7 ${DEFAULT_TERRAFORM_VERSION}" && \
+RUN AVAILABLE_TERRAFORM_VERSIONS="0.11.15 0.12.31 0.13.7 0.14.9 0.15.5 1.0.10 1.1.9 1.2.9 1.3.7 1.4.6 1.5.2" && \
     case "${TARGETPLATFORM}" in \
         "linux/amd64") TERRAFORM_ARCH=amd64 ;; \
         "linux/arm64") TERRAFORM_ARCH=arm64 ;; \
@@ -49,11 +45,10 @@ RUN AVAILABLE_TERRAFORM_VERSIONS="0.11.15 0.12.31 0.13.7 0.14.9 0.15.5 1.0.10 1.
         ln -s "/usr/local/bin/tf/versions/${VERSION}/terraform" "/usr/local/bin/terraform${VERSION}" && \
         rm "terraform_${VERSION}_linux_${TERRAFORM_ARCH}.zip" && \
         rm "terraform_${VERSION}_SHA256SUMS"; \
-    done && \
-    ln -s "/usr/local/bin/tf/versions/${DEFAULT_TERRAFORM_VERSION}/terraform" /usr/local/bin/terraform
+    done
 
 # renovate: datasource=github-releases depName=open-policy-agent/conftest
-ENV DEFAULT_CONFTEST_VERSION=0.38.0
+ENV DEFAULT_CONFTEST_VERSION=0.44.1
 
 RUN AVAILABLE_CONFTEST_VERSIONS="${DEFAULT_CONFTEST_VERSION}" && \
     case "${TARGETPLATFORM}" in \