Remove record publication email templates

* they're not needed anymore since we switched to the generic
  notification builder in Invenio-Config-TUW

invenio_theme_tuw/theme/templates/semantic-ui/invenio_theme_tuw/mails/record_published.html

-{#-
-  Copyright (C) 2024 TU Wien.
-
-  Invenio Theme TUW is free software; you can redistribute it and/or modify
-  it under the terms of the MIT License; see LICENSE file for more details.
--#}
-{%- if record.pids and record.pids.doi %}
-    {%- set doi = record.pids.doi.identifier %}
-    {%- set doi_base_url = "https://doi.org/" if not app.config["DATACITE_TEST_MODE"] else "https://handle.test.datacite.org/"  %}
-    {%- set doi_ref = "DOI" if not app.config["DATACITE_TEST_MODE"] else "DOI-like handle"  %}
-    {%- set avail_message = 'It is now available under the following ' + doi_ref + ': <a href="' + doi_base_url + doi + '">' + doi_base_url + doi + '</a>' %}
-{%- else %}
-    {%- set avail_message = 'It is now available under the following URL: <a href="' + record.links.self_html + '">' + record.links.self_html + '</a>' %}
-{%- endif %}
-<p>
-  Dear {{ uploader.user_profile.full_name }},
-</p>
-<p>
-  Your record "{{ record.metadata.title }}" just got published!
-  <br />
-  {{ avail_message|safe }}
-</p>
-<p>
-  Metadata edits for this record will <em>not</em> require another review.
-</p>
-<p>
-  Cheers,
-  <br />
-  The team at the Center for Research Data Management
-</p>

invenio_theme_tuw/theme/templates/semantic-ui/invenio_theme_tuw/mails/record_published.txt

-{#-
-  Copyright (C) 2024 TU Wien.
-
-  Invenio Theme TUW is free software; you can redistribute it and/or modify
-  it under the terms of the MIT License; see LICENSE file for more details.
--#}
-{%- if record.pids and record.pids.doi %}
-    {%- set doi = record.pids.doi.identifier %}
-    {%- set doi_base_url = "https://doi.org/" if not app.config["DATACITE_TEST_MODE"] else "https://handle.test.datacite.org/"  %}
-    {%- set doi_ref = "DOI" if not app.config["DATACITE_TEST_MODE"] else "DOI-like handle"  %}
-    {%- set avail_message = "It is now available under the following " + doi_ref + ": " + doi_base_url + doi %}
-{%- else %}
-    {%- set avail_message = "It is now available under the following URL: " + record.links.self_html %}
-{%- endif %}
-Dear {{ uploader.user_profile.full_name }},
-
-Your record "{{ record.metadata.title }}" just got published!
-{{ avail_message|safe }}
-
-Metadata edits for this record will *not* require another review.
-
-Cheers,
-The team at the Center for Research Data Management