docs: update README installation instructions

[YOU54F]

• npm run dist works locally (this will run tests, lint and build)
• Commit messages are ready to go in the changelog (see below for details)
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From slack discussion

https://pact-foundation.slack.com/archives/C9VBGLUM9/p1652174044653219

installation instructions should advise to install in devDeps

[mefellows]

I think it should just be -D

[YOU54F]

I think it should just be -D

Doh!

I actually wanted to be verbose, as in the other commands, with --save-dev and suggest -D as short-hand as not every user, especially newbies understand. I didn't when I started in the ecosystem

[YOU54F]

Hmm. The build is failing on one of the examples

https://github.com/pact-foundation/pact-js/runs/6370766697?check_suite_focus=true#step:4:1214

Disconnected reconnect failed before timeout of 2000ms (transport close)

This is an awfully short timeout

10 05 2022 13:30:58.776:INFO [karma-pact]: Pact Mock Server running on port: 1234
10 05 2022 13:30:58.818:INFO [karma-server]: Karma v6.3.16 server started at http://localhost:9876/
10 05 2022 13:30:58.819:INFO [launcher]: Launching browsers Chrome_without_security with concurrency unlimited
10 05 2022 13:30:58.824:INFO [launcher]: Starting browser ChromeHeadless
10 05 2022 13:31:00.561:INFO [Chrome Headless 78.0.3882.0 (Linux x86_64)]: Connected on socket 6_VkRWeufE5oqchsAAAB with id 5119395
Chrome Headless 78.0.3882.0 (Linux x86_64): Executed 0 of 4 SUCCESS (0 secs / 0 secs)
INFO: 'Setting up Pact using mock service on port: "1234"'
Chrome Headless 78.0.3882.0 (Linux x86_64): Executed 0 of 4 SUCCESS (0 secs / 0 secs)
10 05 2022 13:31:04.041:WARN [Chrome Headless 78.0.3882.0 (Linux x86_64)]: Disconnected (0 times) reconnect failed before timeout of 2000ms (transport close)
Chrome Headless 78.0.3882.0 (Linux x86_64) ERROR
  Disconnected reconnect failed before timeout of 2000ms (transport close)
Chrome Headless 78.0.3882.0 (Linux x86_64): Executed 0 of 4 DISCONNECTED (3.282 secs / 0 secs)
Chrome Headless 78.0.3882.0 (Linux x86_64): Executed 0 of 4 DISCONNECTED (3.282 secs / 0 secs)
[2022-05-10 13:31:04.070 +0000] INFO (2979 on fv-az451-700): pact-node@10.17.2: Removing all Pact servers.
[2022-05-10 13:31:04.071 +0000] INFO (2979 on fv-az451-700): pact-node@10.17.2: Removing Pact process with PID: 2986
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! pact-js-karma@1.0.0 test:mocha: `karma start ./mocha/karma.conf.js`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the pact-js-karma@1.0.0 test:mocha script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

[mefellows]

Let's merge this in and fix the timeout issue separately.