Remove $ signs from terminal code examples

[bidoubiwa]

Following these issues #99 and #102, README.md should be updated like this

1. Remove $ in front of command lines

closes: #99
example: meilisearch/meilisearch-js/pull/827
As stated in de markdownlint recommendetation, $ should not be displayed if no output of the commands are showed.

Example:

Wrong ❌: no output, no $ signs

$ ls
$ cat foo
$ less bar

Correct: ✅

ls
cat foo
less bar

Correct: ✅. As there are output, there should be a $ signed to

$ ls
foo bar
$ cat foo
Hello world
$ cat bar
baz

These dollar signs should be removed from the following files:

• README.md
• CONTRIBUTING.md
• .code-samples.meilisearch.yaml
• any other markdown file in a sub directory

TODO

Remove $

• meilisearch-dotnet
• meilisearch-go
• meilisearch-java
• meilisearch-js
• meilisearch-php
• meilisearch-python
• meilisearch-ruby
• meilisearch-rust
• meilisearch-swift
• Laravel Scout
• .Net
• Dart
• Symfony
• Angular
• React
• Vue
• VuePress plugin
• instant-meilisearch
• docs-searchbar.js
• meilisearch-digitalocean
• meilisearch-aws
• meilisearch-kubernetes
• Cloud Scripts
• docs-scraper
• meilisearch-wordpress

[curquiza]

For the $ issue, I will use an automated tool 🙂 I know it might not work everywhere like in the Rust SDK repo, so thanks a lot @sanders41 for this PR (meilisearch/meilisearch-rust#117)