[enh] Improve send_identity.py example

Pass the key to get_identity_document()
Rename the file to 'send_identity' for consistency with the other files
4 jobs for rework_send_membership_identity_documents in 4 minutes and 17 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Format
passed #40187
format

00:00:25

 
  Test
passed #40189
check

00:03:27

passed #40188
test

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  Build
passed #40190
build

00:00:24