update pod command curl to strip ellipsis if it exists

[mh013370]

Q	A
Bug fix?	yes
New feature?	no
API breaks?	no
Deprecations?	no
License	Apache 2.0

What's in this PR?

After upgrading to nifikop v1.7.0, the following was observed during pod startup for a headless NifiCluster:

Waiting for host to be reachable
failed to reach nifi-1-node.nifi-headless.nifi.svc.cluster.local:8443
Found: 1.2.3.4..., expecting: 1.2.3.4

I am running a custom NiFi image, so i believe this could be due to the curl version in the OS. I found that it was v7.29.0.

I ran the following tests to ensure this will handle both of the following cases:

user $ echo "Trying 1.2.3.4..." | awk '{gsub(/\.\.\./, ""); print $2}'
1.2.3.4
user $ echo "Trying 1.2.3.4" | awk '{gsub(/\.\.\./, ""); print $2}'
1.2.3.4

Checklist

• [x] Implementation tested
• [x] Error handling code meets the guideline
• [x] Logging code meets the guideline
• [x] User guide and development docs updated (if needed)
• [x] Append changelog with changes

[mh013370]

It looks like curl always outputs the ellipsis now (and has for a while): https://github.com/curl/curl/blob/cb343182b7181c6df57e7bb711e418ae447fd443/lib/cf-socket.c#L1003

So this change would handle most, if not all, versions of curl used in the NiFi image used.