Update instructions on checking if sim runs with ogre 1.x

[iche033]

🦟 Bug fix

Summary

The instructions for checking if sim runs with ogre 1.x is outdated. The lights.sdf world used to have gui configurations to use the ogre render engine but that was removed in gazebosim/gz-sim#278. Now the user has to explicitly specify the --render-engine ogre arg to run with ogre 1.x.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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