updated docker tagging and readme (#4)

README.md

@@ -112,7 +112,9 @@ Run one of the following commands:
 `yarn release-minor` // increments the `minor` number of the version  
 `yarn release-major` // increments the `major` number of the version
 
-After these commands are executed, make sure to create a tag with matching version number (e.g. matching `v${npm_package_version}`), and push this to the repository.
+After these commands are executed, make sure to create a tag with matching version number (e.g. matching `v${npm_package_version}`), and push this to the repository, e.g:  
+`git tag -a vX.Y.Z -m "vX.Y.Z"`  
+`git push --tags`  
 This causes the CI/CD to create a tagged docker image for both the API and the dashboard with this version number.
 
 ## License

gha/build-container.sh

@@ -7,10 +7,10 @@ set -Eeuxo pipefail
 if [[ $REF_TYPE == "tag" ]]; then
     # we're running on tag creation, set DOCKER_TAG to that tag
     # make sure that the tag specified is valid
-    DOCKER_TAG=`echo $REF_NAME | sed 's/[^a-zA-Z0-9]/-/g'`
+    DOCKER_TAG=`echo $REF_NAME | sed 's/[^a-zA-Z0-9\._-]/-/g'`
 else # we're running on a branch
     # create a valid docker tag name from the branch name
-    VALID_BRANCH_NAME=`echo $REF_NAME | sed 's/[^a-zA-Z0-9]/-/g'`
+    VALID_BRANCH_NAME=`echo $REF_NAME | sed 's/[^a-zA-Z0-9\._-]/-/g'`
     # if the branch is master, create an image using 'latest', otherwise the valid branch name
     if [[ $VALID_BRANCH_NAME == "master" ]]; then
         DOCKER_TAG=latest