go-toolset:rhel8 security, bug fix, and enhancement update

Go Toolset provides the Go programming language tools and libraries. Go is alternatively known as golang.

The following packages have been upgraded to a later upstream version: golang (1.16.7).

Security Fix(es):

* golang: net: lookup functions may return invalid host names (CVE-2021-33195)
* golang: net/http/httputil: ReverseProxy forwards connection headers if first one is empty (CVE-2021-33197)
* golang: math/big.Rat: may cause a panic or an unrecoverable fatal error if passed inputs with very large exponents (CVE-2021-33198)
* golang: net/http/httputil: panic due to racy read of persistConn after handler panic (CVE-2021-36221)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

CVE-2021-33195
Go before 1.15.13 and 1.16.x before 1.16.5 has functions for DNS lookups that do not validate replies from DNS servers, and thus a return value may contain an unsafe injection (e.g., XSS) that does not conform to the RFC1035 format.
CVE-2021-33197
In Go before 1.15.13 and 1.16.x before 1.16.5, some configurations of ReverseProxy (from net/http/httputil) result in a situation where an attacker is able to drop arbitrary headers.
CVE-2021-33198
In Go before 1.15.13 and 1.16.x before 1.16.5, there can be a panic for a large exponent to the math/big.Rat SetString or UnmarshalText method.
CVE-2021-36221
Go before 1.15.15 and 1.16.x before 1.16.7 has a race condition that can lead to a net/http/httputil ReverseProxy panic upon an ErrAbortHandler abort.

Modularity name: go-toolset
Stream name: rhel8