1. fix output dir error in README. (#126)

Author: Gujiawei-Edinburgh

README.md

@@ -131,7 +131,7 @@ mvn wrapper:wrapper
 ./mvnw -U clean package
 ```
 
-The build output consists of several archive files located under `/build/build-bifromq-starters/target/`
+The build output consists of several archive files located under `/target/output`
 
 * `bifromq-<VERSION>-windows-standalone.zip`
 * `bifromq-<VERSION>-standalone.tar.gz`

README.zh_Hans.md

@@ -123,7 +123,7 @@ mvn wrapper:wrapper
 ./mvnw -U clean package
 ```
 
-构建输出位于`/build/build-bifromq-starters/target/`下：
+构建输出位于`/target/output`下：
 
 * `bifromq-<VERSION>-windows-standalone.zip`
 * `bifromq-<VERSION>-standalone.tar.gz`