Adapt emba integration

Adapt emba integration

* admin/notes/emba: Improve docker call.

* test/infra/Dockerfile.emba (emacs-eglot, emacs-tree-sitter):
Install also gawk.

* test/infra/Makefile.in (TREE-SITTER-FILES): New variable.
(tree-sitter-files-template): New rule.
(.PHONY, generate-test-jobs): Add it to dependencies.

* test/infra/gitlab-ci.yml (variables): Disable CI_DEBUG_TRACE.
(test-tree-sitter): Extends also .tree-sitter-files-template.  Use
$tree_sitter_files.

* test/infra/test-jobs.yml: Regenerate.