public GrantedOAuth2AccessTokenBuilder tokenType(String tokenType) {
        this.tokenType = requireNonNull(tokenType, "tokenType");
        return this;
    }
{@value OAuth2Constants#TOKEN_TYPE} Access Token response field,
REQUIRED. The type of the token issued as described at
<a href="https://datatracker.ietf.org/doc/html/rfc6749#section-7.1">[RFC6749], Section 7.1</a>.
Value is case insensitive.
oauth2/src/main/java/com/linecorp/armeria/common/auth/oauth2/GrantedOAuth2AccessTokenBuilder.java