fix(vertexai): add missing quote to chat role error message

[dlarocque]

Add missing closing single quote to error message.

Is a changeset necessary here?

[changeset-bot]

⚠️ No Changeset found

Latest commit: b490c66

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

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[google-oss-bot]

Size Report ¹

Affected Products

• @firebase/vertexai

  Type	Base (9952dbc)	Merge (37dbc2f)	Diff
  browser	34.7 kB	34.7 kB	+1 B (+0.0%)
  main	35.7 kB	35.7 kB	+1 B (+0.0%)
  module	34.7 kB	34.7 kB	+1 B (+0.0%)

• firebase

  Type	Base (9952dbc)	Merge (37dbc2f)	Diff
  firebase-vertexai.js	28.3 kB	28.3 kB	+1 B (+0.0%)

Test Logs

• Base (9952dbc): https://github.com/firebase/firebase-js-sdk/actions/runs/14646189506
• Merge (37dbc2f): https://github.com/firebase/firebase-js-sdk/actions/runs/14712431260

1. https://storage.googleapis.com/firebase-sdk-metric-reports/MrvJzccxnq.html

[google-oss-bot]

Size Analysis Report ¹

Affected Products

• @firebase/vertexai

  • ChatSession

    Size

    Type	Base (9952dbc)	Merge (37dbc2f)	Diff
    size	15.8 kB	15.8 kB	+1 B (+0.0%)
    size-with-ext-deps	34.7 kB	34.7 kB	+1 B (+0.0%)

  • GenerativeModel

    Size

    Type	Base (9952dbc)	Merge (37dbc2f)	Diff
    size	18.9 kB	18.9 kB	+1 B (+0.0%)
    size-with-ext-deps	37.9 kB	37.9 kB	+1 B (+0.0%)

  • getGenerativeModel

    Size

    Type	Base (9952dbc)	Merge (37dbc2f)	Diff
    size	19.1 kB	19.1 kB	+1 B (+0.0%)
    size-with-ext-deps	38.1 kB	38.1 kB	+1 B (+0.0%)

Test Logs

• Base (9952dbc): https://github.com/firebase/firebase-js-sdk/actions/runs/14646189506
• Merge (37dbc2f): https://github.com/firebase/firebase-js-sdk/actions/runs/14712431260

1. https://storage.googleapis.com/firebase-sdk-metric-reports/EAE2VnVPSI.html

[hsubox76]

Add missing closing single quote to error message.

Is a changeset necessary here?

You need a changeset or the package won't publish during the release. Since we will already have a changeset for Vertex due to the Firebase AI PR, it will be fine, but if this was the only Vertex change during this release cycle, you would need it or it wouldn't publish.