chore: fix minor README issues

README.adoc

@@ -31,7 +31,7 @@ Tebako containers are available with different base images to suit various needs
 To package your application from inside the Tebako container, follow these steps:
 
 . Pull the Tebako container image:
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+
 [source,sh]
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 docker pull ghcr.io/tamatebako/amd64-tebako-<container_tag>:latest
@@ -63,23 +63,20 @@ docker run -it --rm -v $PWD:/mnt/w ghcr.io/tamatebako/amd64-tebako-<container_ta
 tebako press --root=/mnt/w/fontist --entry-point=fontist --output=/mnt/w/fontist-package --Ruby=3.2.4
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 == Packaging from Outside the Container
 
 You can also package your application from outside the container by running a single Docker command.
 This command mounts the GitHub workspace into the container and runs the `tebako press` command, specifying the application root, entry point, output location, and Ruby version.
 
 [source,sh]
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-docker run -v <application_folder>:/mnt/w -t ghcr.io/tamatebako/amd64-tebako-${{ matrix.container }}:latest \
+docker run -v <application_folder>:/mnt/w -t ghcr.io/tamatebako/amd64-tebako-<container_tag>:latest \
                    tebako press <tebako press parameters>
 ----
 +
-
 For example, assuming that you have a Ruby application in the `fontist` folder of the current folder, you can package it to ./fontist-package using the following command:
 [source,sh]
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         docker run -v $PWD:/mnt/w -t ghcr.io/tamatebako/amd64-tebako-ubuntu-20.04:latest \
                    tebako press --root=/mnt/w/fontist --entry-point=fontist --output=/mnt/w/fontist-package --Ruby=3.2.4
 ----
-+