[Bug] MineMeld responder domain IOC incorrect type

[colin-stubbs]

Describe the bug

Incorrect case used when assigning IOC type in MineMeld responder.

To Reproduce

Try to use MineMeld responder, experience fail.

Expected behavior

Try to use MineMeld responder, do not experience fail.

Complementary information

diff --git a/responders/Minemeld/minemeld.py b/responders/Minemeld/minemeld.py
index 84285c9..5d569bc 100755
--- a/responders/Minemeld/minemeld.py
+++ b/responders/Minemeld/minemeld.py
@@ -40,7 +40,7 @@ class Minemeld(Responder):
        elif self.observable_type == "url":
          indicator_type = "URL"
        elif self.observable_type == "domain":
-         indicator_type = "Domain"
+         indicator_type = "domain"
        
        # Check for comment
        if self.observable_description == "":

Work environment

• Client OS: n/a
• Server OS: n/a
• Browse type and version: n/a
• Cortex version:
• Cortex Analyzer/Responder name: minemeld
• Cortex Analyzer/Responder version:

Possible solutions

Accept pull request when submitted.

Additional context

n/a

[colin-stubbs]

Refer to schema here: https://github.com/PaloAltoNetworks/minemeld-core/blob/master/docs/schema-indicator-0-1.json

In particular type node,

"type": {
            "description": "type of the indicator",
            "type": "string",
            "enum": [
                "IPv4",
                "IPv6",
                "domain",
                "URL",
                "sha512",
                "sha256",
                "sha1",
                "md5",
                "ssdeep",
                "mutex",
                "windows-registry-value",
                "user-agent.fragment",
                "file.name",
                "process.command_line",
                "email-addr",
                "autonomous-system"
            ]
        },