Update README install step to reference npm package

[tcarmet]

While viewing the package now hosted on npm, noticed something that might be worth correcting.

Feel free to close the PR if I made a mistake or open a suggestion.

[bert-e]

Hello tcarmet,

My role is to assist you with the merge of this
pull request. Please type @bert-e help to get information
on this process, or consult the user documentation.

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[bert-e]

Waiting for approval

The following approvals are needed before I can proceed with the merge:

• the author

• one peer

Peer approvals must include at least 1 approval from the following list:

• @nicolas2bert

• @MonPote

• @ChengYanJin

• @rachedbenmustapha

• @JBWatenbergScality

• @hervedombya

[bert-e]

Waiting for approval

The following approvals are needed before I can proceed with the merge:

• the author

• one peer

Peer approvals must include at least 1 approval from the following list:

• @rachedbenmustapha

• @ChengYanJin

• @MonPote

• @nicolas2bert

• @hervedombya

• @JBWatenbergScality

[MonPote]

Thx @tcarmet :)

[tcarmet]

/approve

[bert-e]

In the queue

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relevant queue(s). The queue(s) will be merged in the target development
branch(es) as soon as builds have passed.

The changeset will be merged in:

• ✔️ development/1.0

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[bert-e]

I have successfully merged the changeset of this pull request
into targetted development branches:

• ✔️ development/1.0

Please check the status of the associated issue None.

Goodbye tcarmet.