Contributing: `./bin/publish` is running into git-related errors

When my local staging branch is up-to-date with hyperledger:staging at https://github.com/hyperledger/education-cryptomoji/commit/ef2d224deeeacc361fcbedf015454db6570f4be5, I'm trying to run ./bin/publish.

Here's the entire output that shows git-related errors:

~/code/hrr-staff/education-cryptomoji$ ./bin/publish
Already on 'staging'
Your branch is up-to-date with 'upstream/staging'.
From github.com:hyperledger/education-cryptomoji
 * branch            staging    -> FETCH_HEAD
Already up-to-date.
Problemifying: /Users/robinkim/code/hrr-staff/education-cryptomoji/code
error: Your local changes to the following files would be overwritten by checkout:
    code/part-one/blockchain.js
    code/part-one/mining.js
    code/part-one/signing.js
    code/part-one/validation.js
    code/part-two/client/source/index.jsx
    code/part-two/client/source/services/addressing.js
    code/part-two/client/source/services/encoding.js
    code/part-two/client/source/services/signing.js
    code/part-two/client/source/services/transactions.js
    code/part-two/processor/handler.js
    code/part-two/processor/services/addressing.js
    code/part-two/processor/services/encoding.js
Please commit your changes or stash them before you switch branches.
Aborting
[staging 7985a02] Problemified code generated from: ef2d224deeeacc361fcbedf015454db6570f4be5
 30 files changed, 2154 deletions(-)
 delete mode 100644 code/part-two/client/source/App.jsx
 delete mode 100644 code/part-two/client/source/Auth.jsx
 delete mode 100644 code/part-two/client/source/Collection.jsx
 delete mode 100644 code/part-two/client/source/CollectionList.jsx
 delete mode 100644 code/part-two/client/source/Moji.jsx
 delete mode 100644 code/part-two/client/source/MojiItem.jsx
 delete mode 100644 code/part-two/client/source/NavBar.jsx
 delete mode 100644 code/part-two/client/source/Offer.jsx
 delete mode 100644 code/part-two/client/source/OfferList.jsx
 delete mode 100644 code/part-two/client/source/ResponseList.jsx
 delete mode 100644 code/part-two/client/source/services/requests.js
 delete mode 100644 code/part-two/processor/actions/accept_response.js
 delete mode 100644 code/part-two/processor/actions/add_response.js
 delete mode 100644 code/part-two/processor/actions/breed_moji.js
 delete mode 100644 code/part-two/processor/actions/cancel_offer.js
 delete mode 100644 code/part-two/processor/actions/create_collection.js
 delete mode 100644 code/part-two/processor/actions/create_offer.js
 delete mode 100644 code/part-two/processor/actions/select_sire.js
Everything up-to-date
Already on 'staging'
Your branch is ahead of 'upstream/staging' by 1 commit.
  (use "git push" to publish your local commits)
Solutionifying: /Users/robinkim/code/hrr-staff/education-cryptomoji/code
Switched to branch 'solution'
On branch solution
nothing to commit, working tree clean
Everything up-to-date
Switched to branch 'staging'
Your branch is ahead of 'upstream/staging' by 1 commit.
  (use "git push" to publish your local commits)

https://github.com/hyperledger/education-cryptomoji/blob/master/bin/publish#L29 seems to be the issue. First, I confirmed that my local master branch is up-to-date with hyperledger:master. However,git checkout master seems to be failing as evidenced by:

error: Your local changes to the following files would be overwritten by checkout:
    code/part-one/blockchain.js
    code/part-one/mining.js
    code/part-one/signing.js
    code/part-one/validation.js
    code/part-two/client/source/index.jsx
    code/part-two/client/source/services/addressing.js
    code/part-two/client/source/services/encoding.js
    code/part-two/client/source/services/signing.js
    code/part-two/client/source/services/transactions.js
    code/part-two/processor/handler.js
    code/part-two/processor/services/addressing.js
    code/part-two/processor/services/encoding.js
Please commit your changes or stash them before you switch branches.
Aborting

Therefore, the problemified commit is created on the staging branch instead, as evidenced by my output from git log --oneline:

~/code/hrr-staff/education-cryptomoji$ git log --oneline
7985a02 (HEAD -> staging) Problemified code generated from: ef2d224deeeacc361fcbedf015454db6570f4be5
ef2d224 (upstream/staging) Merge pull request #91 from therobinkim/client-sires
b0672d3 (origin/client-sires, client-sires) Fix Bootstrap styling for <Collection /> rendering <MojiItem />s

hyperledger-archives / education-cryptomoji

Contributing: `./bin/publish` is running into git-related errors #102