UPSTREAM: 31353: fix env key-value pair matching

Related BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1369679

Passing key-value pairs to `oc set env` with certain invalid characters
causes an unrelated error to be rendered. This is caused because the
regex that separates key-value pairs from resource-type/resource
arguments does not account for invalid key-value pairs with invalid
characters (other than "-"). This means that when a command such as
`oc set env rc/node-1 test#abc=1234` is executed, `test#abc=1234`
will not be recognized as a key-value pair, and instead be treated
as a resource without a resource type, giving a user the wrong reason
for command failure.

This patch updates the regex matching env key-value pairs to match
any character from the beginning of the arg to the equal sign rather
than a select amount of characters, ensuring that key-value pair
arguments with any kind of invalid character are still recognized as
such.

\##### Before
`$ oc set env rc/node-1 test-@abc=1234`
```
there is no need to specify a resource type as a separate argument when
passing arguments in resource/name form (e.g. 'oc get
resource/<resource_name>' instead of 'oc get resource
resource/<resource_name>'
```

\##### After
`$ oc set env rc/node-1 test@-abc=1234`
```
error: ReplicationController "node-1" is invalid:
spec.template.spec.containers[0].env[3].name: Invalid value:
"test@-abc": must be a C identifier (matching regex
[A-Za-z_][A-Za-z0-9_]*): e.g. "my_name" or "MyName"
```

Author: juanvallejo

pkg/cmd/util/env.go

@@ -41,7 +41,7 @@ func GetEnv(key string) (string, bool) {
 
 type Environment map[string]string
 
-var argumentEnvironment = regexp.MustCompile("(?ms)^([\\w\\-_]+)\\=(.*)$")
+var argumentEnvironment = regexp.MustCompile("(?ms)^((.*)+)\\=(.*)$")
 
 func IsEnvironmentArgument(s string) bool {
 	return argumentEnvironment.MatchString(s)