Resolve "Fix/improve elasticsearch password look-up command documentation"

General MR

Summary

Trivial fixes to the kubectl command in the dev doc used to lookup the elastic user's password.

Relevant logs/screenshots

Before (bash), no line break after password output:

$ kubectl get secrets -n logging logging-ek-es-elastic-user -o go-template='{{.data.elastic | base64decode}}'
I5AH3eRA3Gf7oU78T68EO0E8bash-3.2$

After (bash):

$ kubectl get secrets -n logging logging-ek-es-elastic-user -o go-template='{{.data.elastic | base64decode}}' | xargs echo
I5AH3eRA3Gf7oU78T68EO0E8

Before (zsh), % character added to end of output:

$ kubectl get secrets -n logging logging-ek-es-elastic-user -o go-template='{{.data.elastic | base64decode}}'             
I5AH3eRA3Gf7oU78T68EO0E8%

After (zsh), no % character to avoid copying/pasting:

$ kubectl get secrets -n logging logging-ek-es-elastic-user -o go-template='{{.data.elastic | base64decode}}' | xargs echo 
I5AH3eRA3Gf7oU78T68EO0E8

Linked Issue

#186 (closed)

Upgrade Notices

N/A

Closes #186 (closed)