Update README.md (#131)

see https://github.com/apache/skywalking-cli/pull/106#discussion_r684621030
diff --git a/README.md b/README.md
index 95c1dfd..e8e81f2 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@
 Install the latest version with the following command:
 
 ```shell
-/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/apache/skywalking-cli/tree/master/scripts/install.sh)"
+/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/apache/skywalking-cli/master/scripts/install.sh)"
 ```
 
 #### Windows
@@ -29,7 +29,7 @@
 Note: you need to start cmd or powershell in administrator mode.
 
 ```shell
-curl -LO "https://raw.githubusercontent.com/apache/skywalking-cli/tree/master/scripts/install.bat" && .\install.bat
+curl -LO "https://raw.githubusercontent.com/apache/skywalking-cli/master/scripts/install.bat" && .\install.bat
 ```
 
 ### Install by available binaries