Register entry point for each class (Task, Socket, Property)

[superstar54]

Register an entry point for each class, including Task, Socket and Property instead of a list of classes. Suggested naming rule for entry points:

• Format: {package_name}.{short_name_for_class}. If the plugin name starts with 'aiida', such as 'aiida-xxx', you may omit 'aiida' for brevity, e.g., 'xxx.add'. Aim to maintain consistency with the name used when registering with the AiiDA registry.
• The name is case-insensitive, thus xxx.add is the same as xxx.Add.
• Naming Style: Use snake case. For instance, use 'xxx.test_add' for the class 'TestAddTask'. Typically, the suffix 'task' is unnecessary, thus avoid using 'xxx.test_add_task'.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 89.57529% with 27 lines in your changes missing coverage. Please review.

Project coverage is 75.74%. Comparing base (5937b88) to head (f59263a). Report is 9 commits behind head on main.

Files	Patch %	Lines
aiida_workgraph/tasks/builtins.py	84.00%	24 Missing :warning:
aiida_workgraph/tasks/test.py	94.28%	2 Missing :warning:
aiida_workgraph/decorator.py	95.23%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #209 +/- ## ========================================== - Coverage 75.75% 75.74% -0.01% ========================================== Files 70 69 -1 Lines 4615 4696 +81 ========================================== + Hits 3496 3557 +61 - Misses 1119 1139 +20 ``` | [Flag](https://app.codecov.io/gh/aiidateam/aiida-workgraph/pull/209/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=aiidateam) | Coverage Δ | | |---|---|---| | [python-3.11](https://app.codecov.io/gh/aiidateam/aiida-workgraph/pull/209/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=aiidateam) | `75.63% <89.57%> (-0.03%)` | :arrow_down: | | [python-3.9](https://app.codecov.io/gh/aiidateam/aiida-workgraph/pull/209/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=aiidateam) | `75.71% <89.57%> (-0.03%)` | :arrow_down: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=aiidateam#carryforward-flags-in-the-pull-request-comment) to find out more.

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