Add missing Encoding APIs docs

[tarekgh]

Summary

Add missing docs of the following APIs:

M:System.Text.CodePagesEncodingProvider.GetEncodings
T:System.Text.EncodingExtensions
M:System.Text.EncodingExtensions.GetBytes   (System.Text.Encoding,System.ReadOnlySpan{System.Char},   System.Buffers.IBufferWriter{System.Byte})
M:System.Text.EncodingProvider.GetEncodings

[tarekgh]

CC @carlossanlop

[opbld33]

Docs Build status updates of commit fafdfda:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Text/CodePagesEncodingProvider.xml	✅Succeeded	View
xml/System.Text/Encoding.xml	✅Succeeded	View
xml/System.Text/EncodingExtensions.xml	✅Succeeded	View
xml/System.Text/EncodingProvider.xml	✅Succeeded	View

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

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[opbld30]

Docs Build status updates of commit 466c5f0:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Text/CodePagesEncodingProvider.xml	✅Succeeded	View
xml/System.Text/Encoding.xml	✅Succeeded	View
xml/System.Text/EncodingExtensions.xml	✅Succeeded	View
xml/System.Text/EncodingProvider.xml	✅Succeeded	View

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

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[opbld32]

Docs Build status updates of commit 5d6997b:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Text/CodePagesEncodingProvider.xml	✅Succeeded	View
xml/System.Text/Encoding.xml	✅Succeeded	View
xml/System.Text/EncodingExtensions.xml	✅Succeeded	View
xml/System.Text/EncodingProvider.xml	✅Succeeded	View

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

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[opbld32]

Docs Build status updates of commit f1e88c1:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Text/CodePagesEncodingProvider.xml	✅Succeeded	View
xml/System.Text/Encoding.xml	✅Succeeded	View
xml/System.Text/EncodingExtensions.xml	✅Succeeded	View
xml/System.Text/EncodingProvider.xml	✅Succeeded	View

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

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[pgovind]

Just agree with the simplification that @carlossanlop proposed in 1 comment. Otherwise this is looking good.

[opbld33]

Docs Build status updates of commit 58203bb:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Text/CodePagesEncodingProvider.xml	✅Succeeded	View
xml/System.Text/Encoding.xml	✅Succeeded	View
xml/System.Text/EncodingExtensions.xml	✅Succeeded	View
xml/System.Text/EncodingProvider.xml	✅Succeeded	View

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

• Try searching in the Docs contributor and Admin Guide
• See the frequently asked questions
• Post your question in the Docs support channel

[opbld31]

Docs Build status updates of commit 795e5da:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Text/CodePagesEncodingProvider.xml	✅Succeeded	View
xml/System.Text/Encoding.xml	✅Succeeded	View
xml/System.Text/EncodingExtensions.xml	✅Succeeded	View
xml/System.Text/EncodingProvider.xml	✅Succeeded	View

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

• Try searching in the Docs contributor and Admin Guide
• See the frequently asked questions
• Post your question in the Docs support channel

[opbld32]

Docs Build status updates of commit 5fa468c:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Text/CodePagesEncodingProvider.xml	✅Succeeded	View
xml/System.Text/Encoding.xml	✅Succeeded	View
xml/System.Text/EncodingExtensions.xml	✅Succeeded	View
xml/System.Text/EncodingProvider.xml	✅Succeeded	View

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

• Try searching in the Docs contributor and Admin Guide
• See the frequently asked questions
• Post your question in the Docs support channel