UnhandledPromiseRejectionWarning: Unhandled promise rejection

```
? Select what you desire patch
(node:54883) UnhandledPromiseRejectionWarning: Error: From gitlab.com/
! [rejected] v1.0.0 -> v1.0.0 (would clobber existing tag)

at Object.action (/Users/gableroux/.npm-packages/lib/node_modules/@gableroux/git-bump/node_modules/simple-git/src/lib/plugins/error-detection.plugin.js:30:33)
at PluginStore.exec (/Users/gableroux/.npm-packages/lib/node_modules/@gableroux/git-bump/node_modules/simple-git/src/lib/plugins/plugin-store.js:21:33)
at /Users/gableroux/.npm-packages/lib/node_modules/@gableroux/git-bump/node_modules/simple-git/src/lib/runners/git-executor-chain.js:95:45
at new Promise ()
at GitExecutorChain.handleTaskData (/Users/gableroux/.npm-packages/lib/node_modules/@gableroux/git-bump/node_modules/simple-git/src/lib/runners/git-executor-chain.js:93:16)
at GitExecutorChain. (/Users/gableroux/.npm-packages/lib/node_modules/@gableroux/git-bump/node_modules/simple-git/src/lib/runners/git-executor-chain.js:77:46)
at Generator.next ()
at fulfilled (/Users/gableroux/.npm-packages/lib/node_modules/@gableroux/git-bump/node_modules/simple-git/src/lib/runners/git-executor-chain.js:5:58)
at processTicksAndRejections (internal/process/task_queues.js:95:5)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:54883) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 2)
(node:54883) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
```

```
node --version
v14.19.2
```

Reproduce the reported tag-conflict scenario with Node v14.19.2 and trace the CLI's promise handling around the git operation. The stack points into node_modules/@gableroux/git-bump/node_modules/simple-git/src/lib/plugins/error-detection.plugin.js:30; done means the tag conflict is handled without an unhandled-promise warning.

Written by the indexing model from the issue text.