Cookie without Value Parsing Regression in v7.0.4

#### Support plan

* *is this issue currently blocking your project?* (yes/no): yes
* *is this issue affecting a production system?* (yes/no): yes

#### Context

* *node version*: v14
* *module version with issue*: 7.0.4
* *last module version without issue*: 7.0.3
* *environment* (e.g. node, browser, native): node
* *used with* (e.g. hapi application, another framework, standalone, ...): hapi application
* *any other relevant information*: n/a

#### What are you trying to achieve or the steps to reproduce?

1. Send cookie without value in the mid of http cookie header, then the validation fails.
```
cookie: key1=value1; key2; key3=value3
```
2. It works if key2 is at the end of cookie header
```
cookie: key1=value1; key2
```

#### What was the result you got?
```
Server Error Log: Invalid cookie name: key2; key3
```

#### What result did you expect?
```
The exact same cookie header works in 7.0.3
```