Fix typo in name of flag

Signed-off-by: Nokome Bentley <[email protected]>

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Author: nokome

content/docs/app-developer-guide/using-cache-image.md

@@ -19,7 +19,7 @@ The `--cache-image` parameter must be in the following format
 --cache-image <remote-image-location>
 ```
 
-The `--cache-images` flag must be specified in conjunction with the `--publish` flag.
+The `--cache-image` flag must be specified in conjunction with the `--publish` flag.
 
 ### Examples
 For the following examples we will use:
@@ -85,4 +85,4 @@ pack build localhost:5000/buildpack-examples/second-cache-image-example \
 ```
 <!--+- "{{execute}}"+-->
 
-[samples]: https://github.com/buildpack/samples
+[samples]: https://github.com/buildpack/samples