Don't require too old mbed-os-tools

Patater · Patater · commit 3fcb0e7a7bf4 · 2020-11-09T09:52:05.000Z
mbed-os-tools 1.8.0 is as compatible with 0.0.9 as 0.0.15 was. Remove
the "not greater than" bound on the mbed-os-tools version.
diff --git a/requirements.txt b/requirements.txt
@@ -1,2 +1,2 @@
 pyserial>=3.0,<4.0
-mbed-os-tools>=0.0.9,<0.1.0
+mbed-os-tools>=0.0.9
