Merge pull request #8075 from OPpuolitaival/requirements

Syncronize mbed-ls minimum version with icetea requirements

Author: Cruz Monrreal

requirements.txt

@@ -6,7 +6,7 @@ IntelHex>=1.3
 junit-xml
 pyYAML
 requests
-mbed-ls>=1.4.2,==1.*
+mbed-ls>=1.5.1,==1.*
 mbed-host-tests>=1.1.2
 mbed-greentea>=0.2.24
 beautifulsoup4>=4