Fix SNMPv3 password configuration (#1122)

* Add SNMPInflight metric (#1119)

* Add SNMPInflight metric

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Signed-off-by: Kakuya Ando <fservak@gmail.com>
Signed-off-by: Robert Bergman <rob.bergman@gmail.com>

* change #1074 broke SNMPv3 by removing the lines that need to go in config.go after 155 and 171 respectively:
usm.AuthenticationPassphrase = string(c.Password)

and

usm.PrivacyPassphrase = string(c.PrivPassword)

after adding the back in to the code, I tried running with having variables set via environment and in the snmp.yml and both worked. without them I was getting the error:

securityParameter.PrivacyPassphrase is required when a privacy protocol is specified

Signed-off-by: Robert Bergman <rob.bergman@gmail.com>

---------

Signed-off-by: Kakuya Ando <fservak@gmail.com>
Signed-off-by: Robert Bergman <rob.bergman@gmail.com>
Co-authored-by: Kakuya Ando <fservak@gmail.com>

config/config.go

@@ -153,6 +153,7 @@ func (c Auth) ConfigureSNMP(g *gosnmp.GoSNMP) {
 		priv = true
 	}
 	if auth {
+		usm.AuthenticationPassphrase = string(c.Password)
 		switch c.AuthProtocol {
 		case "SHA":
 			usm.AuthenticationProtocol = gosnmp.SHA
@@ -169,6 +170,7 @@ func (c Auth) ConfigureSNMP(g *gosnmp.GoSNMP) {
 		}
 	}
 	if priv {
+		usm.PrivacyPassphrase = string(c.PrivPassword)
 		switch c.PrivProtocol {
 		case "DES":
 			usm.PrivacyProtocol = gosnmp.DES