sendgrid-go inbound.Parse fails with panic when Content-Type is text/html

[m-terel]

I've set up Inbound Email Parse Webhook. In the webhook I use https://github.com/sendgrid/sendgrid-go lib.

inbound.Parse method fails with a panic for some of the received HTTP requests. It fails when the Content-Type of the received HTTP request is "text/html; charset=utf-8". It works only for multipart content types.

address or nil pointer dereference

goroutine 67 [running]:
runtime/debug.Stack(0xc0003394b8, 0xb5c0c0, 0x1207480)
	/usr/local/go/src/runtime/debug/stack.go:24 +0x9f
github.com/GoogleCloudPlatform/functions-framework-go/funcframework.recoverPanicHTTP(0xd38be0, 0xc0002881c0, 0xc58b92, 0xe)
	/workspace/serverless_function_source_code/vendor/github.com/GoogleCloudPlatform/functions-framework-go/funcframework/framework.go:52 +0x76
panic(0xb5c0c0, 0x1207480)
	/usr/local/go/src/runtime/panic.go:965 +0x1b9
mime/multipart.(*Reader).nextPart(0x0, 0xc00068a300, 0xc0006748d5, 0x18, 0x0)
	/usr/local/go/src/mime/multipart/multipart.go:319 +0x37
mime/multipart.(*Reader).NextPart(...)
	/usr/local/go/src/mime/multipart/multipart.go:306
github.com/sendgrid/sendgrid-go/helpers/inbound.(*ParsedEmail).parseRawEmail(0xc00068a0c0, 0xc000674000, 0x82df, 0x7, 0x126ade0)
	/workspace/serverless_function_source_code/vendor/github.com/sendgrid/sendgrid-go/helpers/inbound/inbound.go:56 +0x375
github.com/sendgrid/sendgrid-go/helpers/inbound.(*ParsedEmail).parse(0xc00068a0c0, 0xc00068a0c0, 0xc0002f7380)
	/workspace/serverless_function_source_code/vendor/github.com/sendgrid/sendgrid-go/helpers/inbound/inbound.go:41 +0x134
github.com/sendgrid/sendgrid-go/helpers/inbound.Parse(0xc000306b00, 0x1, 0xc0002f7408, 0x419d01)
	/workspace/serverless_function_source_code/vendor/github.com/sendgrid/sendgrid-go/helpers/inbound/inbound.go:26 +0x9e
...