Test issue to ensure non spamming of comments

### Description of defect

The first run was without this description and all the other fields were empty. The 'new' template comment was written. Test was run several times to ensure no further comments were added. Second test will involves updating this description and filling in a couple of fields.

#### Target(s) affected by this defect ?
K64F

#### Toolchain(s) (name and version) displaying this defect ?
ARMCC6

#### What version of Mbed-os are you using (tag or sha) ?
mbed-os-5.15.0

#### What version(s) of tools are you using. List all that apply (E.g. mbed-cli)
mbed-cli v20

#### How is this defect reproduced ?

Just run the git2jira script multiple times

Start by locating the git2jira script and reviewing how it detects and updates comments for issue 42. Run the script repeatedly, then update the issue description and fields as described. Done means repeated runs do not add duplicate comments while still reflecting the intended template update.

Written by the indexing model from the issue text.