Do not check for changes in getters

[gtirloni]

Fixes #104

It doesn't make sense to check for changes when reading values from resource_data.

E.g. email_template.template is never changed but we need to read it to be passed to the API during the update.

This successfully fixed the bug for me and I was able to update the email templates as expected.

Tested with terraform 0.12.7

$ make testacc
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test $(go list ./...) -v  -timeout 120m -coverprofile="c.out" -run ^".*"$
?   	github.com/alexkappa/terraform-provider-auth0	[no test files]
=== RUN   TestProvider
--- PASS: TestProvider (0.00s)
=== RUN   TestProvider_debugDefaults
=== RUN   TestProvider_debugDefaults/should_be_false_when_AUTH0_DEBUG_environment_variable_is_set_to_"false"
=== RUN   TestProvider_debugDefaults/should_be_false_if_no_AUTH0_DEBUG_environment_variable_is_defined
=== RUN   TestProvider_debugDefaults/should_be_true_when_AUTH0_DEBUG_environment_variable_is_set_to_"1"
=== RUN   TestProvider_debugDefaults/should_be_true_when_AUTH0_DEBUG_environment_variable_is_set_to_"true"
=== RUN   TestProvider_debugDefaults/should_be_true_when_AUTH0_DEBUG_environment_variable_is_set_to_"on"
--- PASS: TestProvider_debugDefaults (0.00s)
    --- PASS: TestProvider_debugDefaults/should_be_false_when_AUTH0_DEBUG_environment_variable_is_set_to_"false" (0.00s)
    --- PASS: TestProvider_debugDefaults/should_be_false_if_no_AUTH0_DEBUG_environment_variable_is_defined (0.00s)
    --- PASS: TestProvider_debugDefaults/should_be_true_when_AUTH0_DEBUG_environment_variable_is_set_to_"1" (0.00s)
    --- PASS: TestProvider_debugDefaults/should_be_true_when_AUTH0_DEBUG_environment_variable_is_set_to_"true" (0.00s)
    --- PASS: TestProvider_debugDefaults/should_be_true_when_AUTH0_DEBUG_environment_variable_is_set_to_"on" (0.00s)
=== RUN   TestAccClientGrant
--- PASS: TestAccClientGrant (5.42s)
=== RUN   TestAccClient
--- PASS: TestAccClient (3.04s)
=== RUN   TestAccConnection
--- PASS: TestAccConnection (4.82s)
=== RUN   TestAccConnectionAd
--- PASS: TestAccConnectionAd (2.76s)
=== RUN   TestAccConnectionWaad
--- PASS: TestAccConnectionWaad (2.80s)
=== RUN   TestAccConnectionWithEnbledClients
--- PASS: TestAccConnectionWithEnbledClients (18.08s)
=== RUN   TestAccCustomDomain
--- SKIP: TestAccCustomDomain (0.00s)
    resource_auth0_custom_domain_test.go:12: 
=== RUN   TestAccEmailTemplate
--- PASS: TestAccEmailTemplate (4.04s)
=== RUN   TestAccEmail
--- PASS: TestAccEmail (2.71s)
=== RUN   TestAccResourceServer
--- PASS: TestAccResourceServer (2.66s)
=== RUN   TestAccRuleConfig
--- PASS: TestAccRuleConfig (2.52s)
=== RUN   TestAccRule
--- PASS: TestAccRule (2.50s)
=== RUN   TestRuleNameRegexp
--- PASS: TestRuleNameRegexp (0.00s)
=== RUN   TestAccTenant
--- PASS: TestAccTenant (2.79s)
=== RUN   TestAccUserMissingRequiredParams
--- PASS: TestAccUserMissingRequiredParams (0.01s)
=== RUN   TestAccUserCreateUser
--- PASS: TestAccUserCreateUser (2.49s)
=== RUN   TestMapData
--- PASS: TestMapData (0.00s)
PASS
coverage: 76.9% of statements
ok  	github.com/alexkappa/terraform-provider-auth0/auth0	56.678s	coverage: 76.9% of statements

[github-actions]

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[alexkappa]

@gtirloni changes to the resource data code is quite risky to change at the moment. The lack of update tests in our test suite makes this a little hard to illustrate but the HasChange is there for a reason. The issue referenced is resolved differently however by merging #144.

[gtirloni]

Understood, thank you.