Add core-method tests for http confirmations & wallet chain options

[cgewecke]

Description

Adds some additional test coverage to web3-core-method for:

• confirmations over http
• method calls made with a wallet address using the default chain, hardfork and common options

Because of the 1s polling interval, am only testing confirmations with geth automine.

Type of change

• Tests

Checklist:

• I have selected the correct base branch.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• Any dependent changes have been merged and published in downstream modules.
• I ran npm run dtslint with success and extended the tests and types if necessary.
• I ran npm run test:unit with success and extended the tests if necessary.
• I ran npm run build-all and tested the resulting file/'s from dist folder in a browser.
• I have updated the CHANGELOG.md file in the root folder.
• I have tested my code on the live network.

[coveralls]

Coverage increased (+0.4%) to 85.36% when pulling 0bf0bc9 on test/conf-http into 3f839c9 on 1.x.

[nivida]

LGTM!