search: The component_templates do not need to specify the SEARCH_IND…

[psaiz]

Currently, all templates need to define the SEARCH_INDEX_PREFIX. Otherwise, uploading the template fails. This makes sense for index_templates, and not for component templates.
This patch makes sure that the components are not required to specify the prefix.

[psaiz]

This is how the execution looks like:

There is no need for 'Putting templates' (no items specified)
Putting component templates...
  [------------------------------------]    0%/opt/invenio/var/instance/python/lib/python3.9/site-packages/invenio_search/ext.py:467: UserWarning: You are using the prefix `opendata-dev-v007-`, but the template `/code/cernopendata/modules/search/component_templates/os-v2/opendata-docs-v1.0.0.json` does not contain the pattern `__SEARCH_INDEX_PREFIX__`.
  warnings.warn(message)

/code/cernopendata/modules/search/component_templates/os-v2/opendata-docs-v1.0.0.json  [#########---------------------------]   25%/opt/invenio/var/instance/python/lib/python3.9/site-packages/invenio_search/ext.py:467: UserWarning: You are using the prefix `opendata-dev-v007-`, but the template `/code/cernopendata/modules/search/component_templates/os-v2/opendata-glossary-term-v1.0.0.json` does not contain the pattern `__SEARCH_INDEX_PREFIX__`.
  warnings.warn(message)

/code/cernopendata/modules/search/component_templates/os-v2/opendata-glossary-term-v1.0.0.json  [##################------------------]   50%/opt/invenio/var/instance/python/lib/python3.9/site-packages/invenio_search/ext.py:467: UserWarning: You are using the prefix `opendata-dev-v007-`, but the template `/code/cernopendata/modules/search/component_templates/os-v2/opendata-record-v1.0.0.json` does not contain the pattern `__SEARCH_INDEX_PREFIX__`.
  warnings.warn(message)

/code/cernopendata/modules/search/component_templates/os-v2/opendata-record-v1.0.0.json  [###########################---------]   75%       /opt/invenio/var/instance/python/lib/python3.9/site-packages/invenio_search/ext.py:467: UserWarning: You are using the prefix `opendata-dev-v007-`, but the template `/code/cernopendata/modules/search/component_templates/os-v2/opendata-common-v1.0.0.json` does not contain the pattern `__SEARCH_INDEX_PREFIX__`.
  warnings.warn(message)

/code/cernopendata/modules/search/component_templates/os-v2/opendata-common-v1.0.0.json  [####################################]  100%       
Putting index templates...
/code/cernopendata/modules/search/index_templates/os-v2/opendata-glossary-term-v1.0.0.json  [####################################]  100%
There is no need for 'Creating indexes' (no items specified)

[slint]

LGTM, two tiny nits, but otherwise we can merge and relase.