Simplify README (#1789)

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### Summary

After the Qiskit 0.44.0 release the qiskit-metapackage is only
installing qiskit-terra now. This commit updates the readme to reflect
this. Previously it was still referring to the other elements being
installed in the metapackage.

### Details and comments

README.md

@@ -22,32 +22,8 @@ build from source standalone versions of the individual Qiskit elements and comp
 
 ## Qiskit Packaging
 
-The Qiskit project used to be made up of many components. However, in the future the Qiskit metapackage will only install [**Qiskit Terra**](https://github.com/Qiskit/qiskit-terra):
-
-| Build   | Version | Contribute |
-| ---     | --- | --- |
-| [**Qiskit Terra**](https://github.com/Qiskit/qiskit-terra) | [![](https://img.shields.io/github/release/Qiskit/qiskit-terra.svg?)](https://github.com/Qiskit/qiskit-terra/releases)  | [![](https://img.shields.io/github/forks/Qiskit/qiskit-terra.svg?)](https://github.com/Qiskit/qiskit-terra) |
-
-<table>
-  <tr>
-    <td colspan="3" align="center">:warning: WARNING :warning:</br> <b>For the time being, two other packages are installed, but these components will be removed from the metapackage in a future release.</b></td>
-  </tr>
-<tr>
-<th>Build</th>
-<th>Version</th>
-<th>Contribute</th>
-</tr>
-<tr>
-<td><a href="https://github.com/Qiskit/qiskit-aer"><strong>Qiskit Aer</strong></a></td>
-<td><a href="https://github.com/Qiskit/qiskit-aer/releases"><img src="https://camo.githubusercontent.com/7b4ebed2975693dc2d18233e49b7f9141838c1e86f22ac36f465fcd3886821b6/68747470733a2f2f696d672e736869656c64732e696f2f6769746875622f72656c656173652f5169736b69742f7169736b69742d6165722e7376673f" alt="" data-canonical-src="https://img.shields.io/github/release/Qiskit/qiskit-aer.svg?"></a></td>
-<td><a href="https://github.com/Qiskit/qiskit-aer"><img src="https://camo.githubusercontent.com/ced831707852701ae4c21b1455d6c2d2a03fa54dffe09fcf5208970112023a05/68747470733a2f2f696d672e736869656c64732e696f2f6769746875622f666f726b732f5169736b69742f7169736b69742d6165722e7376673f" alt="" data-canonical-src="https://img.shields.io/github/forks/Qiskit/qiskit-aer.svg?"></a></td>
-</tr>
-<tr>
-<td><a href="https://github.com/Qiskit/qiskit-ibmq-provider"><strong>Qiskit IBM Quantum Provider</strong></a></td>
-<td><a href="https://github.com/Qiskit/qiskit-ibmq-provider/releases"><img src="https://camo.githubusercontent.com/daa12aee2f03d2d310bd6ad1a5c5babe99b038fc08ad9f0309f5e1c7420c9ffe/68747470733a2f2f696d672e736869656c64732e696f2f6769746875622f72656c656173652f5169736b69742f7169736b69742d69626d712d70726f76696465722e7376673f" alt="" data-canonical-src="https://img.shields.io/github/release/Qiskit/qiskit-ibmq-provider.svg?"></a></td>
-<td><a href="https://github.com/Qiskit/qiskit-ibmq-provider"><img src="https://camo.githubusercontent.com/49f1938883f91358a594feeddecdd59b3188a353a9a20721a6fefcd64c32f6ce/68747470733a2f2f696d672e736869656c64732e696f2f6769746875622f666f726b732f5169736b69742f7169736b69742d69626d712d70726f76696465722e7376673f" alt="" data-canonical-src="https://img.shields.io/github/forks/Qiskit/qiskit-ibmq-provider.svg?"></a></td>
-</tr>
-</table>
+The Qiskit project used to be made up of many components. However, it is now only comprised of the [**Qiskit Terra**](https://github.com/Qiskit/qiskit-terra)
+project and the Qiskit meta-package contained in this repository only installs that.
 
 ### Using quantum services