glossary: fix descrption about isolation

[hfxsd]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-09-05 01:17:51.263545441 +0000 UTC m=+493595.781598697: ☑️ agreed by Oreoxmt.

[hfxsd]

/approve

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.1: #18537.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.2: #18538.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.3: #18539.