Small fix to check for complex synapse in create_dense

[Michaeljurado42]

Issue Number: 129

Objective of pull request: The check for a complex synapse fails in create_dense

Pull request checklist

Your PR fulfills the following requirements:

• Issue created that explains the change and why it's needed
• Tests are part of the PR (for bug fixes / features)
• Docs reviewed and added / updated if needed (for bug fixes / features)
• PR conforms to Coding Conventions
• PR applys BSD 3-clause or LGPL2.1+ Licenses to all code files
• Lint (flakeheaven lint src/lava tests/) and (bandit -r src/lava/.) pass locally
• Build tests (pytest) passes locally

Pull request type

Please check your PR type:

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

What is the current behavior?

In hdf5.py there is a line like this:

        if isinstance(layer_config["weight"], NetDict):

What is the new behavior?

        if "weight/imag" in layer_config.f:

Does this introduce a breaking change?

• Yes
• No

Supplemental information

This bug is the cause of an experimental change I made to a lava-dl fork which I forgot to remove.

Previously in a discussion post, @bamsumit discussed the possibility of having a complex_synapse key which would be used in this if-statement. However, adding this complex synapse key means that the current unit test ground truth data with .net files would have to be re-generated since they do not have this key.

This bug-fix removes the complex_synapse key and fixes the if statement that checks for complex synapses. More info given in the issue.

[Michaeljurado42]

I re-used an a previous fork for this PR. Is that okay, or should I create a new fork just for the specific change?

[bamsumit]

Looks good