[main < E-merge] Create merge query module

[mpintaric55334]

Description

• Merge relationships with dynamic type and with different properties depending on whether the relationship was matched or created PR395
• Merge nodes with dynamic type and with different properties depending on whether the node was matched or created PR391

Pull request type

• Bugfix
• Algorithm/Module
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

Related issues

Delete if this PR doesn't resolve any issues. Link the issue if it does.

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Reviewer checklist (the reviewer checks this part)

Module/Algorithm

• Core algorithm/module implementation
• Query module implementation
• Unit tests
• End-to-end tests
• Code documentation
• README short description
• Documentation on memgraph/docs
• Update GQLALchemy signatures in query builder using query module signature generator

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