Update branches build status in README (#950)

* Add branch build status for v4.x/ps7.4

* Remove build status for Functions versions no longer supported

* Update target branches

Author: Francisco-Gamino

README.md

@@ -3,11 +3,9 @@
 |Branch|Status|
 |---|---|
 |dev|[![Build Status](https://dev.azure.com/azfunc/Azure%20Functions/_apis/build/status/Azure.azure-functions-powershell-worker?branchName=dev)](https://dev.azure.com/azfunc/Azure%20Functions/_build/latest?definitionId=21&branchName=dev)|
-|v4.x/ps7.2|[![Build Status](https://dev.azure.com/azfunc/Azure%20Functions/_apis/build/status/Azure.azure-functions-powershell-worker?branchName=v3.x%2Fps7)](https://dev.azure.com/azfunc/Azure%20Functions/_build/latest?definitionId=21&branchName=v4.x%2Fps7.2)|
-|v4.x/ps7.0|[![Build Status](https://dev.azure.com/azfunc/Azure%20Functions/_apis/build/status/Azure.azure-functions-powershell-worker?branchName=v3.x%2Fps7)](https://dev.azure.com/azfunc/Azure%20Functions/_build/latest?definitionId=21&branchName=v4.x%2Fps7.0)|
-|v3.x/ps7|[![Build Status](https://dev.azure.com/azfunc/Azure%20Functions/_apis/build/status/Azure.azure-functions-powershell-worker?branchName=v3.x%2Fps7)](https://dev.azure.com/azfunc/Azure%20Functions/_build/latest?definitionId=21&branchName=v3.x%2Fps7)|
-|v3.x/ps6|[![Build Status](https://dev.azure.com/azfunc/Azure%20Functions/_apis/build/status/Azure.azure-functions-powershell-worker?branchName=v3.x%2Fps6)](https://dev.azure.com/azfunc/Azure%20Functions/_build/latest?definitionId=21&branchName=v3.x%2Fps6)|
-|v2.x|[![Build Status](https://dev.azure.com/azfunc/Azure%20Functions/_apis/build/status/Azure.azure-functions-powershell-worker?branchName=v2.x)](https://dev.azure.com/azfunc/Azure%20Functions/_build/latest?definitionId=21&branchName=v2.x)|
+|v4.x/ps7.4|[![Build Status](https://dev.azure.com/azfunc/Azure%20Functions/_apis/build/status/Azure.azure-functions-powershell-worker?branchName=v4.x%2Fps7.4)](https://dev.azure.com/azfunc/Azure%20Functions/_build/latest?definitionId=21&branchName=v4.x%2Fps7.4)|
+|v4.x/ps7.2|[![Build Status](https://dev.azure.com/azfunc/Azure%20Functions/_apis/build/status/Azure.azure-functions-powershell-worker?branchName=v4.x%2Fps7.2)](https://dev.azure.com/azfunc/Azure%20Functions/_build/latest?definitionId=21&branchName=v4.x%2Fps7.2)|
+|v4.x/ps7.0|[![Build Status](https://dev.azure.com/azfunc/Azure%20Functions/_apis/build/status/Azure.azure-functions-powershell-worker?branchName=v4.x%2Fps7.0)](https://dev.azure.com/azfunc/Azure%20Functions/_build/latest?definitionId=21&branchName=v4.x%2Fps7.0)|
 
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