Addition of ER EntityKeyTable and bug fixes

[mavaylon1]

Motivation

What was the reasoning behind this change? Please explain the changes briefly.

1. Addition of EntityKeyTable and related methods/tests
2. Fixed bug where reusing a key object wouldn't be recorded in ObjectKeyTable

How to test the behavior?

Show how to reproduce the new behavior (can be a bug fix or a new feature)

Checklist

• Did you update CHANGELOG.md with your changes?
• Have you checked our Contributing document?
• Have you ensured the PR clearly describes the problem and the solution?
• Is your contribution compliant with our coding style? This can be checked running ruff from the source directory.
• Have you checked to ensure that there aren't other open Pull Requests for the same change?
• Have you included the relevant issue number using "Fix #XXX" notation where XXX is the issue number? By including "Fix #XXX" you allow GitHub to close issue #XXX when the PR is merged.

[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.01 🎉

Comparison is base (f81537c) 88.19% compared to head (07a42c2) 88.20%.

Additional details and impacted files

@@            Coverage Diff             @@
##              dev     #872      +/-   ##
==========================================
+ Coverage   88.19%   88.20%   +0.01%     
==========================================
  Files          44       44              
  Lines        9022     9032      +10     
  Branches     2577     2587      +10     
==========================================
+ Hits         7957     7967      +10     
+ Misses        753      752       -1     
- Partials      312      313       +1     

Impacted Files	Coverage Δ
src/hdmf/common/io/resources.py	100.00% <100.00%> (ø)
src/hdmf/common/resources.py	97.23% <100.00%> (-0.47%)	⬇️

... and 1 file with indirect coverage changes

☔ View full report in Codecov by Sentry.
📢 Do you have feedback about the report comment? Let us know in this issue.

[rly]

Suggested change

	if not int(idx) < keys.__len__():
	if int(idx) >= len(keys):

[rly]

same for this and the other uses of len above (sorry I didn't catch these earlier)

[rly]

can you update the other three uses of __len__ in this file?

[mavaylon1]

Done

[oruebel]

@mavaylon1 there are a few places in the plot_external_resources.py tutorial that should be updated to also list the new table:

• hdmf/docs/gallery/plot_external_resources.py

  Lines 38 to 39 in 07a42c2

  	* :py:class:`~hdmf.common.resources.EntityTable` where each row describes an
  	:py:class:`~hdmf.common.resources.Entity`

• https://github.com/hdmf-dev/hdmf/blob/07a42c295f7843832dd724aa9a6bcd5f8828e39a/docs/gallery/plot_external_resources.py#L211C1-L211C1