Update node-fetch related packages

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
@types/node-fetch	devDependencies	minor	^2.1.4 -> ^2.5.0
node-fetch	devDependencies	minor	^2.1.2 -> ^2.6.0
node-fetch	dependencies	minor	^2.1.2 -> ^2.6.0
node-fetch	dependencies	minor	^2.0.0 -> ^2.6.0

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Release Notes

bitinn/node-fetch

v2.6.0

Compare Source

• Enhance: options.agent, it now accepts a function that returns custom http(s).Agent instance based on current URL, see readme for more information.
• Fix: incorrect Content-Length was returned for stream body in 2.5.0 release; note that node-fetch doesn't calculate content length for stream body.
• Fix: Response.url should return empty string instead of null by default.

v2.5.0

Compare Source

• Enhance: Response object now includes redirected property.
• Enhance: fetch() now accepts third-party Blob implementation as body.
• Other: disable package-lock.json generation as we never commit them.
• Other: dev dependency update.
• Other: readme update.

v2.4.1

Compare Source

• Fix: Blob import rule for node < 10, as Readable isn't a named export.

v2.4.0

Compare Source

• Enhance: added Brotli compression support (using node's zlib).
• Enhance: updated Blob implementation per spec.
• Fix: set content type automatically for URLSearchParams.
• Fix: Headers now reject empty header names.
• Fix: test cases, as node 12+ no longer accepts invalid header response.

v2.3.0

Compare Source

• Enhance: added AbortSignal support, with README example.
• Enhance: handle invalid Location header during redirect by rejecting them explicitly with FetchError.
• Fix: update browser.js to support react-native environment, where self isn't available globally.

v2.2.1

Compare Source

• Fix: compress flag shouldn't overwrite existing Accept-Encoding header.
• Fix: multiple import rules, where PassThrough etc. doesn't have a named export when using node <10 and --exerimental-modules flag.
• Other: Better README.

v2.2.0

Compare Source

• Enhance: Support all ArrayBuffer view types
• Enhance: Support Web Workers
• Enhance: Support Node.js' --experimental-modules mode; deprecate .es.js file
• Fix: Add __esModule property to the exports object
• Other: Better example in README for writing response to a file
• Other: More tests for Agent

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[elasticmachine]

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[spalger]

LGTM

[spalger]

7.4/7.x: 424058b