Bump elasticsearch from 15.5.0 to 16.7.1

[dependabot-preview]

Bumps elasticsearch from 15.5.0 to 16.7.1.

Changelog

Sourced from elasticsearch's changelog.

=== 16.7.1 (Mar 26 2020)

• apiVersions before 7.6 restored after feedback in elastic/elasticsearch-js-legacy#28

=== 16.7.0 (Mar 25 2020)

• apiVersion "7.6" is now the default
• "7.6" is now the only apiVersion in the version 7 major version

=== 16.6.0 (Jan 15 2020)

• apiVersion "7.5" is now the default

=== 16.5.0 (Oct 31 2019)

• apiVersion "7.4" is now the default

=== 16.4.0 (Jul 10 2019)

• apiVersion "7.3" is now the default

=== 16.3.0 (Jul 10 2019)

• Removed many development dependencies
• Switched to standard + prettier linting config. Testing indicates that this doesn't have any effect on the external API but it produces thousands of changes so releasing as a minor version bump just to be safe.

=== 16.2.0 (Jul 3 2019)

• apiVersion "7.2" is now the default
• Dropped support for old 6.7 version

=== 16.1.1 (Jun 4 2019)

• Updated readme

=== 16.1.0 (May 29 2019)

• apiVersion "7.1" is now the default

=== 16.0.0 (May 2 2019)

• apiVersion "7.0" is now the default
• Dropped support for old 6.x versions, and all versions before 5.6

Commits

• 0f81719 version 16.7.1
• 317b77a [api] regenerate
• b5f2e30 restore older apiVersions
• f475fe6 version 16.7.0
• 825aa83 [api] regenerate
• b212b10 add 7.7 support, 7.6 is now default, drop old 7.x versions
• 128ba27 version 16.6.0
• d322a95 [apis] regnerate
• b326e5f add support for 7.6, default to 7.5
• 388c5e8 force replace a bad link in generated docs
• Additional commits viewable in compare view

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[dependabot-preview]

Superseded by #247.