Updated README.md for labgraph folder;

[AlexeyAulov]

Description

The installation for labgraph was wrong on the README.md file in the labgraph folder.

Fixes #(issue)

Type of change

Changed from pip install labgraph
To pip install labgraph==2.0.0

Please delete options that are not relevant.

• This change requires a documentation update

Feature/Issue validation/testing

Please describe the tests [UT/IT] that you ran to verify your changes and relevant result summary. Provide instructions so it can be reproduced.
Please also list any relevant details for your test configuration.

• Test A

• Test B

• Unit Test / Integration Test (UT/IT) execution results

• Logs

Checklist:

• Have you added tests that prove your fix is effective or that this feature works?
• New and existing unit tests pass locally with these changes?
• Has code been commented, particularly in hard-to-understand areas?
• Have you made corresponding changes to the documentation?

[jfResearchEng]

Is the following an intended change: extensions/graphviz_support/graphviz_support/tests/output/test.svg ?

[AlexeyAulov]

Hi, the test.svg file must have been unintentionally pushed, it shouldn't be part of the changes, thank you.