fix: Preserve relationship properties upon refactor.merge_nodes

[ranok]

This diff addresses #3921 by iterating through all the of properties on the relationships that will be deleted and setting them on the newly-added relationships.

Tested on amd64 build of master memgraph and MAGE.

memgraph> CREATE (:PERSON {NAME: "John Doe"})-[:FRIENDS_WITH {LEVEL: "besties"}]->(:PERSON {NAME: "Bob Smith"});
Empty set (round trip in 0.000 sec)
2 labels have been created.
2 nodes have been created.
1 relationships have been created.
memgraph> CREATE (:PERSON {EMAIL: "John@Doe.com"});
Empty set (round trip in 0.000 sec)
1 labels have been created.
1 nodes have been created.
memgraph> MATCH p = ()-[rel]-() RETURN properties(rel);
+--------------------+
| properties(rel)    |
+--------------------+
| {LEVEL: "besties"} |
| {LEVEL: "besties"} |
+--------------------+
2 rows in set (round trip in 0.000 sec)
memgraph> MATCH (p1:PERSON {NAME: "John Doe"}), (p2:PERSON {EMAIL: "John@Doe.com"}) CALL refactor.merge_nodes([p2, p1], {properties: "override", mergeRels: true}) YIELD node RETURN node;
+-----------------------------------------------------+
| node                                                |
+-----------------------------------------------------+
| (:PERSON {EMAIL: "John@Doe.com", NAME: "John Doe"}) |
+-----------------------------------------------------+
1 row in set (round trip in 0.000 sec)
INFO: Sequential scan will be used on symbol `p1` although there is a filter on labels :PERSON and properties NAME. Consider creating a label-property index.
1 labels have been created.
1 nodes have been deleted.
2 properties have been updated.
1 relationships have been created.
1 relationships have been deleted.
memgraph> MATCH p = ()-[rel]-() RETURN properties(rel);
+--------------------+
| properties(rel)    |
+--------------------+
| {LEVEL: "besties"} |
| {LEVEL: "besties"} |
+--------------------+

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  • Fixed propertied on relationships being deleted when running refactor.merge_nodes() - now properties on relationships are preserved. #3948
• [ Documentation PR link memgraph/documentation#XXXX ]
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[ranok]

Added an e2e test for the property preservation to prevent regressions and also rang clang-format on the changed CPP file.

[github-actions]

Staging branch created: staging/8425e9a-master ✔️

CI Diff (External) run here ❌

[github-actions]

Staging branch created: staging/8425e9a ✔️

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[github-actions]

Staging branch created: staging/d112841 ✔️

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[github-actions]

Staging branch created: staging/ccad71a ✔️

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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[mattkjames7]

Looks good to me.

I made some changes to pass the clang-tidy checks. I have also built the image locally to test it, and it works as expected.

I'll place it into the merge queue, should be merged within about an hour.

Nice work! 💪