TextImage methods only supports ReadOnlySpan<byte>

[danielcaceresm]

The provided methods to set image data only supports ReadOnlySpan as parameter.
Would be nice to implements more overloads or a generic method.

At this moment in WaveEngine we have implemented a converter to use the overload that receive a ITypedArray, but will be nice that this conversion is done by the WebGL.Backend and we work with ReadOnlySpan<byte|sbyte|...>.

This is the code of our converter:

    private static unsafe ITypedArray GetData(uint pixelType, void* data, uint sourceSizeInBytes)
    {
        // https://www.khronos.org/registry/webgl/specs/latest/2.0/ under 'void texImage2D' section
        WebAssembly.Core.ITypedArray array;
        switch (pixelType)
        {
            case GLConstants.ColorPointerTypeByte:
                array = WebAssembly.Core.Int8Array.From(new ReadOnlySpan<sbyte>(data, (int)sourceSizeInBytes));
                break;
            case GLConstants.ColorPointerTypeUnsignedByte:
                array = WebAssembly.Core.Uint8Array.From(new ReadOnlySpan<byte>(data, (int)sourceSizeInBytes));
                break;
            case GLConstants.ColorPointerTypeShort:
                array = WebAssembly.Core.Int16Array.From(new ReadOnlySpan<short>(data, (int)sourceSizeInBytes));
                break;
            case GLConstants.ColorPointerTypeUnsignedShort:
            case GLConstants.ExtensionsUnsignedShort565:
            case GLConstants.PixelTypeUnsignedShort5551:
            case GLConstants.PixelTypeUnsignedShort4444:
                array = WebAssembly.Core.Uint16Array.From(new ReadOnlySpan<ushort>(data, (int)sourceSizeInBytes));
                break;
            case GLConstants.ColorPointerTypeInt:
                array = WebAssembly.Core.Int32Array.From(new ReadOnlySpan<int>(data, (int)sourceSizeInBytes));
                break;
            case GLConstants.ColorPointerTypeUnsignedInt:
            case GLConstants.ExtensionsUnsignedInt5999Rev:
            case GLConstants.VertexAttribTypeUnsignedInt2101010Rev:
            case GLConstants.VertexAttribPointerTypeUnsignedInt10f11f11fRev:
            case GLConstants.ExtensionsUnsignedInt248:
                array = WebAssembly.Core.Uint32Array.From(new ReadOnlySpan<uint>(data, (int)sourceSizeInBytes));
                break;
            case GLConstants.VertexAttribPointerTypeHalfFloat:
                array = WebAssembly.Core.Uint16Array.From(new ReadOnlySpan<ushort>(data, (int)sourceSizeInBytes));
                break;
            case GLConstants.VertexAttribPointerTypeFloat:
                array = WebAssembly.Core.Float32Array.From(new ReadOnlySpan<float>(data, (int)sourceSizeInBytes));
                break;
            default:
                array = WebAssembly.Core.Uint8Array.From(new ReadOnlySpan<byte>(data, (int)sourceSizeInBytes));
                break;
        }
        return array;
    }

Thanks!