Fix allowReserved typo in OpenAPIEncoding deserializers for v3 and v31

[Copilot]

Description

This PR fixes a typo in the OpenAPI encoding deserializers where the field name was incorrectly set to "allowedReserved" instead of "allowReserved" (note the extra "d"). This bug prevented the allowReserved property from being properly deserialized from OpenAPI v3.0 and v3.1 documents.

According to the OpenAPI 3.0 specification and OpenAPI 3.1 specification, the correct field name is allowReserved (without the "d").

Changes

Fixed Deserializers

• V3: src/Microsoft.OpenApi/Reader/V3/OpenApiEncodingDeserializer.cs - Changed "allowedReserved" to "allowReserved" (line 47)
• V31: src/Microsoft.OpenApi/Reader/V31/OpenApiEncodingDeserializer.cs - Changed "allowedReserved" to "allowReserved" (line 46)

Added Regression Tests

To prevent future regressions, this PR adds unit tests that specifically verify the allowReserved field is correctly deserialized:

• test/Microsoft.OpenApi.Readers.Tests/V3Tests/OpenApiEncodingTests.cs - Added ParseEncodingWithAllowReservedShouldSucceed test
• test/Microsoft.OpenApi.Readers.Tests/V31Tests/OpenApiEncodingTests.cs - Created new test file with ParseEncodingWithAllowReservedShouldSucceed test
• Sample YAML files demonstrating the allowReserved field for both V3 and V31

Example

Before this fix, the following OpenAPI document would fail to deserialize the allowReserved property:

openapi: 3.0.0
paths:
  /upload:
    post:
      requestBody:
        content:
          application/x-www-form-urlencoded:
            schema:
              type: object
            encoding:
              id:
                contentType: application/x-www-form-urlencoded
                allowReserved: true  # This was ignored due to the typo

After this fix, the AllowReserved property is correctly set to true on the deserialized OpenApiEncoding object.

Testing

• All existing tests pass (1,177 tests total)
• New tests specifically validate allowReserved deserialization for both V3 and V31

Fixes #[issue_number]

Warning

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I tried to connect to the following addresses, but was blocked by firewall rules:

• example.org926f4f21-88e7-4dc5-bf88-6c529bb77844
  • Triggering command: /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/OpenAPI.NET/OpenAPI.NET/test/Microsoft.OpenApi.Hidi.Tests/bin/Debug/net8.0/Microsoft.OpenApi.Hidi.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/OpenAPI.NET/OpenAPI.NET/test/Microsoft.OpenApi.Hidi.Tests/bin/Debug/net8.0/Microsoft.OpenApi.Hidi.Tests.deps.json /home/REDACTED/work/OpenAPI.NET/OpenAPI.NET/test/Microsoft.OpenApi.Hidi.Tests/bin/Debug/net8.0/testhost.dll --port 43161 --endpoint 127.0.0.1:043161 --role client --parentprocessid 4655 --telemetryoptedin false (dns block)
  • Triggering command: /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/OpenAPI.NET/OpenAPI.NET/test/Microsoft.OpenApi.Hidi.Tests/bin/Debug/net8.0/Microsoft.OpenApi.Hidi.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/OpenAPI.NET/OpenAPI.NET/test/Microsoft.OpenApi.Hidi.Tests/bin/Debug/net8.0/Microsoft.OpenApi.Hidi.Tests.deps.json /home/REDACTED/work/OpenAPI.NET/OpenAPI.NET/test/Microsoft.OpenApi.Hidi.Tests/bin/Debug/net8.0/testhost.dll --port 46779 --endpoint 127.0.0.1:046779 --role client --parentprocessid 9482 --telemetryoptedin false (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

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Original prompt

---

This section details on the original issue you should resolve

<issue_title>OpenAPIEncoding property is wrongly "allowedReserved" instead of "allowReserved" in v3 and V31 deserialization</issue_title>
<issue_description>Describe the bug

The deserialization key for the property "allowReserved" is "allowedReserved" which is a typo in v3 and v31. It should be "allowReserved" instead.

Also make sure to add unit test to prevent any further regression.
</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #2517

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[MIchaelMainer]

LGTM