Update TypeLoadException text for Type.GetType

[gewarren]

Contributes to dotnet/docs#39594.

[dotnet-policy-service]

Tagging subscribers to this area: @dotnet/area-system-runtime

[learn-build-service-prod]

Learn Build status updates of commit 3527ce0:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System/Type.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel

[BillWagner]

This LGTM, once you address @jkotas 's feedback.

[learn-build-service-prod]

Learn Build status updates of commit 151838e:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System/Type.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel

[learn-build-service-prod]

Learn Build status updates of commit 678a02c:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System/Type.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel