fix: loosen peerDependencies to document the oldest compatible package

[jgravois]

tl:dr

it has been an error on my part to sync the peerDependencies manually with the devDependencies that lerna bumps automatically. we should be advertising the lowest compatible version, not the most recent.

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@jPurush shared a thread with me the other day that made me realize:

• lerna is making a conscious choice not to bump the peerDependencies for each package
• if it is necessary to bump a peerDependency to exclude a previously compatible version, its likely that a breaking change is being introduced.

for example, we should have tagged v2.0.0 when we landed #400 because we introduced a dependency on a new cleanUrl() method inside the request package in existing functions in other packages.

folks even reported uncaught errors to me when cleanUrl() wasn't found in their own projects that were resolved by upgrading request. i knew enough about what was going on to recommend the fix to people but not enough to realize that we'd broken our contract.

getting in here and trying to figure out exactly what the minimum requirements were for our packages actually made the relationships more clear to me.

besides that, going forward we'll benefit from the lack of rote manual version bumping.

reference:

• Feature: allow updating peerDependencies in version command lerna/lerna#1575 (comment)
• peerDependencies shouldn't be updated by lerna publish lerna/lerna#1018
• example in babel

AFFECTS PACKAGES:
@esri/arcgis-rest-auth
@esri/arcgis-rest-feature-service-admin
@esri/arcgis-rest-feature-service
@esri/arcgis-rest-geocoder
@esri/arcgis-rest-groups
@esri/arcgis-rest-items
@esri/arcgis-rest-routing
@esri/arcgis-rest-sharing
@esri/arcgis-rest-users

[codecov]

Codecov Report

Merging #506 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##           master   #506   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files          95     95           
  Lines        1221   1221           
  Branches      227    227           
=====================================
  Hits         1221   1221

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[noahmulfinger]

@jgravois Just thinking out loud, but I wonder if there's a way we can test packages with both the latest and oldest compatible version of their dependent packages, so stuff like cleanUrl doesn't slip through the cracks.

[jgravois]

i'm still glad i did the research, but this PR is irrelevant now.