CMake apt repository does not support Ubuntu Lunar

[h3ndrk]

I tried building the Devcontainer but got the following error:

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 > [dev_container_auto_added_stage_label 11/19] RUN wget -O - https://apt.kitware.com/keys/kitware-archive-latest.asc 2>/dev/null         | gpg --dearmor - | tee /etc/apt/trusted.gpg.d/kitware.gpg >/dev/null &&     apt-add-repository -y "deb https://apt.kitware.com/ubuntu/ lunar main" &&     apt-get update -qq && export DEBIAN_FRONTEND=noninteractive &&     apt-get install -y --no-install-recommends cmake cmake-curses-gui:
1.764 Hit:1 https://ppa.launchpadcontent.net/ubuntu-toolchain-r/test/ubuntu lunar InRelease
1.770 Hit:2 http://archive.ubuntu.com/ubuntu lunar InRelease
1.779 Hit:3 http://security.ubuntu.com/ubuntu lunar-security InRelease
1.860 Hit:4 http://archive.ubuntu.com/ubuntu lunar-updates InRelease
1.950 Hit:5 http://archive.ubuntu.com/ubuntu lunar-backports InRelease
1.980 Ign:6 https://apt.kitware.com/ubuntu lunar InRelease
2.076 Err:7 https://apt.kitware.com/ubuntu lunar Release
2.076   404  Not Found [IP: 66.194.253.25 443]
2.440 Hit:8 https://apt.llvm.org/lunar llvm-toolchain-lunar-15 InRelease
2.562 Reading package lists...
[2024-02-15T17:33:37.172Z] 
3.365 E: The repository 'https://apt.kitware.com/ubuntu lunar Release' does not have a Release file.
3.365 W: http://apt.llvm.org/lunar/dists/llvm-toolchain-lunar-15/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
3.367 Repository: 'deb https://apt.kitware.com/ubuntu/ lunar main'
3.367 Description:
3.367 Archive for codename: lunar components: main
3.367 More info: https://apt.kitware.com/ubuntu/
3.367 Adding repository.
[2024-02-15T17:33:37.172Z] 3.367 Adding deb entry to /etc/apt/sources.list.d/archive_uri-https_apt_kitware_com_ubuntu_-lunar.list
3.367 Adding disabled deb-src entry to /etc/apt/sources.list.d/archive_uri-https_apt_kitware_com_ubuntu_-lunar.list
5.125 W: http://apt.llvm.org/lunar/dists/llvm-toolchain-lunar-15/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
5.125 E: The repository 'https://apt.kitware.com/ubuntu lunar Release' does not have a Release file.
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[2024-02-15T17:33:37.175Z] Dockerfile-with-features:69
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  68 |     ARG CMAKE_PKG=${VARIANT}
  69 | >>> RUN wget -O - https://apt.kitware.com/keys/kitware-archive-latest.asc 2>/dev/null \
  70 | >>>         | gpg --dearmor - | tee /etc/apt/trusted.gpg.d/kitware.gpg >/dev/null && \
  71 | >>>     apt-add-repository -y "deb ${CMAKE_URL} ${CMAKE_PKG} main" && \
  72 | >>>     apt-get update -qq && export DEBIAN_FRONTEND=noninteractive && \
  73 | >>>     apt-get install -y --no-install-recommends cmake cmake-curses-gui
  74 |     
--------------------

On https://apt.kitware.com/ you can read:

We currently support Ubuntu 20.04 and 22.04 on our repository.

So not 23.04 😉

Changing to jammy fixed it:

diff --git a/.devcontainer/devcontainer.json b/.devcontainer/devcontainer.json
index ebc687b..a393369 100644
--- a/.devcontainer/devcontainer.json
+++ b/.devcontainer/devcontainer.json
@@ -8,11 +8,11 @@
     // Update 'GCC_VER' to pick a gcc and g++ version. Options: [10, 11, 12, 13]. Default: 12
     // Update 'LLVM_VER' to pick clang version. Options: [10, 11, 12, 13, 14, 15]. Default: 15
     // Update 'USE_CLANG' to set clang as the default C and C++ compiler. Options: [1, null]. Default null
-    // "args": {
-    //         "VARIANT": "focal",
-    //         "GCC_VER": "12",
-    //         "LLVM_VER": "15"
-    // }
+    "args": {
+       "VARIANT": "jammy",
+       //"GCC_VER": "12",
+       //"LLVM_VER": "15"
+    }
   },
   "runArgs": [
     "--cap-add=SYS_PTRACE",