Fix dspace-solr Dockerfile parse error

[MMilosz]

References

• Fixes dspace-solr Docker build fails due to multi-line ENV parse error #546

Description

This PR fixes Solr Dockerfile parse error. Currently, it's not possible to run $ docker compose -f docker-compose.yml build --no-cache.

Instructions for Reviewers

How to Reproduce:

1. Remove any existing image 4science/dspace-cris-solr
2. Run docker compose -f docker-compose.yml build --no-cache
3. Observe the following error:

Dockerfile:33

--------------------

  32 |         AUDIT_CONFIGSET_PATH=/opt/solr/server/solr/configsets/audit/conf

  33 | >>>     DEDUP_CONFIGSET_PATH=/opt/solr/server/solr/configsets/dedup/conf \

  34 | >>>     OCR_CONFIGSET_PATH=/opt/solr/server/solr/configsets/ocr/conf \

  35 | >>> 

  36 | >>> USER root

  37 |     

--------------------

target dspacesolr: failed to solve: dockerfile parse error on line 33: unknown instruction: DEDUP_CONFIGSET_PATH=/opt/solr/server/solr/configsets/dedup/conf

How to Test:

1. Ensure you don't have any image 4science/dspace-cris-solr
2. Apply changes from this PR. Run docker compose -f docker-compose.yml build --no-cache

Checklist

• My PR is created against the main branch of code (unless it is a backport or is fixing an issue specific to an older branch).
• My PR is small in size (e.g. less than 1,000 lines of code, not including comments & integration tests). Exceptions may be made if previously agreed upon.
• My PR passes Checkstyle validation based on the Code Style Guide.
• My PR includes Javadoc for all new (or modified) public methods and classes. It also includes Javadoc for large or complex private methods.
• My PR passes all tests and includes new/updated Unit or Integration Tests based on the Code Testing Guide.
• My PR includes details on how to test it. I've provided clear instructions to reviewers on how to successfully test this fix or feature.
• If my PR includes new libraries/dependencies (in any pom.xml), I've made sure their licenses align with the DSpace BSD License based on the Licensing of Contributions documentation.
• If my PR modifies REST API endpoints, I've opened a separate REST Contract PR related to this change.
• If my PR includes new configurations, I've provided basic technical documentation in the PR itself.
• If my PR fixes an issue ticket, I've linked them together.