Add dbus patch for container builds. (#49402)

var/spack/repos/builtin/packages/dbus/meson_post_install.patch

@@ -0,0 +1,9 @@
+diff --git a/meson_post_install.py b/meson_post_install.py
+index cfc03b22..1d007ad6 100755
+--- a/meson_post_install.py
++++ b/meson_post_install.py
+@@ -103,4 +103,3 @@ def post_install_exe():
+ 
+ if __name__ == "__main__":
+     post_install_relocation()
+-    post_install_exe()

var/spack/repos/builtin/packages/dbus/package.py

@@ -42,6 +42,13 @@ class Dbus(AutotoolsPackage, MesonPackage):
     version("1.8.6", sha256="eded83ca007b719f32761e60fd8b9ffd0f5796a4caf455b01b5a5ef740ebd23f")
     version("1.8.4", sha256="3ef63dc8d0111042071ee7f7bafa0650c6ce2d7be957ef0b7ec269495a651ff8")
     version("1.8.2", sha256="5689f7411165adc953f37974e276a3028db94447c76e8dd92efe910c6d3bae08")
+    # Skip function that tries to do something if you're root that doesn't work in a container.
+    # Only tested on 1.15.10, but probably works for other versions as well.
+    patch(
+        "meson_post_install.patch",
+        sha256="d121f842418af606f414ebfc523b51fdd23a2d231e73d66229a4b0ab3486edc4",
+        when="@1.15.10",
+    )
 
     variant("xml_docs", default=False, description="Build XML documentation")
     variant("system-socket", default="default", description="Location for the DBus system socket")