[earthly] Update helm install commands (#676)

Author: tobil4sk

Earthfile

@@ -90,8 +90,8 @@ devcontainer-base:
         && apt-get update \
         && apt-get -y install --no-install-recommends kubectl=1.29.* \
         # install helm
-        && curl -fsSL https://baltocdn.com/helm/signing.asc | apt-key add - \
-        && echo "deb https://baltocdn.com/helm/stable/debian/ all main" | tee /etc/apt/sources.list.d/helm-stable-debian.list \
+        && curl -fsSL https://packages.buildkite.com/helm-linux/helm-debian/gpgkey | gpg --dearmor | tee /usr/share/keyrings/helm.gpg > /dev/null \
+        && echo "deb [signed-by=/usr/share/keyrings/helm.gpg] https://packages.buildkite.com/helm-linux/helm-debian/any/ any main" | tee /etc/apt/sources.list.d/helm-stable-debian.list \
         && apt-get update \
         && apt-get -y install --no-install-recommends helm \
         #