Revert "feat(no-ignored-observable): put back old rule"

This reverts commit 47e1271.

Author: JasonWeinzierl

README.md

@@ -92,7 +92,6 @@ The package includes the following rules.
 | [no-ignored-default-value](docs/rules/no-ignored-default-value.md)     | Disallow using `firstValueFrom`, `lastValueFrom`, `first`, and `last` without specifying a default value. | 🔒   |    |    | 💭 |    |
 | [no-ignored-error](docs/rules/no-ignored-error.md)                     | Disallow calling `subscribe` without specifying an error handler.                                         | 🔒   |    |    | 💭 |    |
 | [no-ignored-notifier](docs/rules/no-ignored-notifier.md)               | Disallow observables not composed from the `repeatWhen` or `retryWhen` notifier.                          | ✅ 🔒 |    |    | 💭 |    |
-| [no-ignored-observable](docs/rules/no-ignored-observable.md)           | Disallow ignoring observables returned by functions.                                                      |      |    |    | 💭 | ❌  |
 | [no-ignored-replay-buffer](docs/rules/no-ignored-replay-buffer.md)     | Disallow using `ReplaySubject`, `publishReplay` or `shareReplay` without specifying the buffer size.      | ✅ 🔒 |    |    |    |    |
 | [no-ignored-subscribe](docs/rules/no-ignored-subscribe.md)             | Disallow calling `subscribe` without specifying arguments.                                                |      |    |    | 💭 |    |
 | [no-ignored-subscription](docs/rules/no-ignored-subscription.md)       | Disallow ignoring the subscription returned by `subscribe`.                                               |      |    |    | 💭 |    |

docs/rules/no-ignored-observable.md

@@ -20,7 +20,6 @@ import { noFloatingObservablesRule } from './rules/no-floating-observables';
 import { noIgnoredDefaultValueRule } from './rules/no-ignored-default-value';
 import { noIgnoredErrorRule } from './rules/no-ignored-error';
 import { noIgnoredNotifierRule } from './rules/no-ignored-notifier';
-import { noIgnoredObservableRule } from './rules/no-ignored-observable';
 import { noIgnoredReplayBufferRule } from './rules/no-ignored-replay-buffer';
 import { noIgnoredSubscribeRule } from './rules/no-ignored-subscribe';
 import { noIgnoredSubscriptionRule } from './rules/no-ignored-subscription';
@@ -68,7 +67,6 @@ const plugin = {
     'no-ignored-default-value': noIgnoredDefaultValueRule,
     'no-ignored-error': noIgnoredErrorRule,
     'no-ignored-notifier': noIgnoredNotifierRule,
-    'no-ignored-observable': noIgnoredObservableRule,
     'no-ignored-replay-buffer': noIgnoredReplayBufferRule,
     'no-ignored-subscribe': noIgnoredSubscribeRule,
     'no-ignored-subscription': noIgnoredSubscriptionRule,