Add badges (!59)

<!--
ICON

---------------------------------------------------------------
Copyright (C) 2004-2024, DWD, MPI-M, DKRZ, KIT, ETH, MeteoSwiss
Contact information: icon-model.org

See AUTHORS.TXT for a list of authors
See LICENSES/ for license information
SPDX-License-Identifier: CC0-1.0
---------------------------------------------------------------
-->

## What is the new feature
Add badges
## How is it implemented
Adding to README. Pipelines for master branch has to be enabled for pipeline and coverage badges to show.
- [x] This MR has to wait for !57



## Mandatory steps before review
- [x] Gitlab CI passes _(Hint: use `make format` for linting)_ 
- [x] New feature is covered by additional unit tests
- [x] Mark the merge request as ready by removing `Draft:`

## Mandatory steps before merge
- [x] Reviewed by a maintainer
- [x] Incorporate review suggestions
- [x] Remember to edit the commit message and select the proper changelog category (feature/bugfix/other)

**You are not supposed to merge this request by yourself, the maintainers of fortan-support take care of this action!**

Merged-by: Jonas Jucker <jonas.jucker@env.ethz.ch>
Changelog: other

.gitlab-ci.yml

@@ -19,7 +19,7 @@ stages:
 workflow:
   rules:
     - if: $CI_PIPELINE_SOURCE == "merge_request_event"
-    - if: $CI_COMMIT_TAG
+    - if: $CI_COMMIT_REF_NAME == "master"
 
 nag:
   stage: build_and_test

README.md

@@ -14,6 +14,14 @@ SPDX-License-Identifier: CC-BY-4.0
 # Fortran-support library
 This repository is an external library of ICON collecting low-level supporting modules of ICON.
 
+[![Latest Release](https://gitlab.dkrz.de/icon-libraries/libfortran-support/-/badges/release.svg)](https://gitlab.dkrz.de/icon-libraries/libfortran-support/-/releases)
+[![pipeline status](https://gitlab.dkrz.de/icon-libraries/libfortran-support/badges/master/pipeline.svg)](https://gitlab.dkrz.de/icon-libraries/libfortran-support/pipelines/latest?ref=master)
+[![coverage report](https://gitlab.dkrz.de/icon-libraries/libfortran-support/badges/master/coverage.svg)](https://gitlab.dkrz.de/icon-libraries/libfortran-support/pipelines/latest?ref=master)  
+[![License](https://img.shields.io/badge/License-BSD_3--Clause-blue.svg)](https://gitlab.dkrz.de/icon-libraries/libfortran-support/-/blob/master/LICENSES/BSD-3-Clause.txt)
+[![License: CC BY 4.0](https://img.shields.io/badge/License-CC_BY_4.0-lightgrey.svg)](https://gitlab.dkrz.de/icon-libraries/libfortran-support/-/blob/master/LICENSES/CC-BY-4.0.txt)
+[![License: CC0-1.0](https://img.shields.io/badge/License-CC0_1.0-lightgrey.svg)](https://gitlab.dkrz.de/icon-libraries/libfortran-support/-/blob/master/LICENSES/CC0-1.0.txt)
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://gitlab.dkrz.de/icon-libraries/libfortran-support/-/blob/master/LICENSES/MIT.txt)
+
 ## Requirements
 The following packages/libraries are required for `libfortran-support`.
 - Fortran compiler