remove: template-no-negated-comparison

This rule has no upstream equivalent in ember-template-lint and its
premise is debatable: `not-eq` is a first-class ember-truth-helpers
helper, so flagging it as wrong is a style opinion rather than a
correctness concern. Additionally, it conflicts conceptually with the
newly-restored `template-no-negated-condition`, which autofixes
`(not (eq ...))` to `not-eq` — the opposite direction.

Opening for NullVoxPopuli to decide.

Author: johanrd

README.md

@@ -249,7 +249,6 @@ rules in templates can be disabled with eslint directives with mustache or html
 | [template-no-model-argument-in-route-templates](docs/rules/template-no-model-argument-in-route-templates.md)       | disallow @model argument in route templates                                  |    | 🔧 |    |
 | [template-no-multiple-empty-lines](docs/rules/template-no-multiple-empty-lines.md)                                 | disallow multiple consecutive empty lines in templates                       |    | 🔧 |    |
 | [template-no-mut-helper](docs/rules/template-no-mut-helper.md)                                                     | disallow usage of (mut) helper                                               |    |    |    |
-| [template-no-negated-comparison](docs/rules/template-no-negated-comparison.md)                                     | disallow negated comparisons in templates                                    |    |    |    |
 | [template-no-negated-condition](docs/rules/template-no-negated-condition.md)                                       | disallow negated conditions in if/unless                                     |    | 🔧 |    |
 | [template-no-nested-splattributes](docs/rules/template-no-nested-splattributes.md)                                 | disallow nested ...attributes usage                                          |    |    |    |
 | [template-no-obscure-array-access](docs/rules/template-no-obscure-array-access.md)                                 | disallow obscure array access patterns like `objectPath.@each.property`      |    | 🔧 |    |