[atkmm] meson.build: Don't use deprecated python3.path()

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 6426dc13fb48449d5abd00c0ec1427e7764bb4df
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Sun Feb 6 10:49:18 2022 +0100

    meson.build: Don't use deprecated python3.path()

 atk/atkmm/meson.build     | 4 ++--
 doc/reference/meson.build | 4 ++--
 meson.build               | 8 ++++----
 3 files changed, 8 insertions(+), 8 deletions(-)
---
diff --git a/atk/atkmm/meson.build b/atk/atkmm/meson.build
index a6b8fcd..bba6238 100644
--- a/atk/atkmm/meson.build
+++ b/atk/atkmm/meson.build
@@ -211,7 +211,7 @@ endif
 
 # Install built .h and _p.h files.
 meson.add_install_script(
-  python3.path(), generate_binding_py, 'install_built_h_files',
+  python3, generate_binding_py, 'install_built_h_files',
   built_h_cc_dir,
   install_includedir / atkmm_pcname / 'atkmm', # subdir below {prefix}
   hg_ccg_basenames
@@ -220,7 +220,7 @@ meson.add_install_script(
 if can_add_dist_script
   # Distribute built files.
   meson.add_dist_script(
-    python3.path(), generate_binding_py, 'dist_built_files',
+    python3, generate_binding_py, 'dist_built_files',
     built_h_cc_dir,
     untracked_atkmm,
     hg_ccg_basenames,
diff --git a/doc/reference/meson.build b/doc/reference/meson.build
index e71d11f..5797e9e 100644
--- a/doc/reference/meson.build
+++ b/doc/reference/meson.build
@@ -141,7 +141,7 @@ devhelp_file = custom_target('devhelp',
 
 # Install Devhelp file and html files.
 meson.add_install_script(
-  python3.path(), doc_reference_py, 'install_doc',
+  python3, doc_reference_py, 'install_doc',
   doctool_dir,
   devhelp_file.full_path(),
   install_devhelpdir,
@@ -152,7 +152,7 @@ meson.add_install_script(
 if can_add_dist_script
   # Distribute built files and files copied by mm-common-get.
   meson.add_dist_script(
-    python3.path(), doc_reference_py, 'dist_doc',
+    python3, doc_reference_py, 'dist_doc',
     doctool_dir,
     doctool_dist_dir,
     meson.current_build_dir(),
diff --git a/meson.build b/meson.build
index 9a98015..f1c83c9 100644
--- a/meson.build
+++ b/meson.build
@@ -6,8 +6,8 @@ project('atkmm', 'cpp',
   default_options: [
     'cpp_std=c++17'
   ],
-  meson_version: '>= 0.54.0', # required for meson.override_dependency()
-                              # and dep.get_variable(internal:)
+  meson_version: '>= 0.55.0', # required for meson.add_dist_script(python3, ...)
+                              # and meson.add_install_script(python3, ...)
 )
 
 atkmm_api_version = '2.36'
@@ -232,13 +232,13 @@ subdir('doc/reference')
 if can_add_dist_script
   # Add a ChangeLog file to the distribution directory.
   meson.add_dist_script(
-    python3.path(), dist_changelog_py,
+    python3, dist_changelog_py,
     project_source_root,
   )
   # Add build scripts to the distribution directory, and delete .gitignore
   # files and an empty $MESON_PROJECT_DIST_ROOT/build/ directory.
   meson.add_dist_script(
-    python3.path(), dist_build_scripts_py,
+    python3, dist_build_scripts_py,
     project_source_root,
     'untracked' / 'build_scripts',
   )