Update rust workflow (#1610)

## Что этот PR делает
В рамках подготовки к мерге апстрима.

.github/workflows/build_milla.yml → .github/workflows/build_rust.yml

@@ -1,13 +1,13 @@
-name: Build MILLA
+name: Build Rust library
 on:
   issue_comment:
     types: created
 
 jobs:
-  build-milla:
+  build-rust:
     if: |
       github.event.issue.pull_request &&
-      (github.event.comment.body == '!build_milla') &&
+      (github.event.comment.body == '!build_rust') &&
       ((github.event.sender.id == github.event.issue.user.id) ||
       (github.event.comment.author_association == 'COLLABORATOR') ||
       (github.event.comment.author_association == 'MEMBER') ||
@@ -53,7 +53,7 @@ jobs:
           ref: ${{ env.PR_BRANCH }}
           token: ${{ env.GH_TOKEN }}
 
-      - name: Build MILLA
+      - name: Build rustlibs
         env:
           BASE_BRANCH: ${{ github.event.repository.default_branch }}
           BASE_REPOSITORY: ${{ github.repository }}
@@ -65,7 +65,7 @@ jobs:
           git pull origin "$PR_BRANCH" --depth=$((ahead_by + 1))
           git remote add upstream "https://github.com/$BASE_REPOSITORY.git"
           git fetch upstream "$BASE_BRANCH" --depth=$((behind_by + 1))
-          cd milla
+          cd rust
 
           # Get dependencies.
           rustup target add i686-unknown-linux-gnu
@@ -79,13 +79,13 @@ jobs:
           cargo build --release --target i686-pc-windows-gnu
 
           # Copy the built targets to their checked-in locations.
-          cp target/i686-unknown-linux-gnu/release/libmilla.so ../tools/ci/libmilla_ci.so
-          cp target/i686-pc-windows-gnu/release/milla.dll ../milla.dll
+          cp target/i686-unknown-linux-gnu/release/librustlibs.so ../tools/ci/librustlibs_ci.so
+          cp target/i686-pc-windows-gnu/release/rustlibs.dll ../rustlibs.dll
 
-          git commit -a -m "Build MILLA" --allow-empty
+          git commit -a -m "Build Rust library" --allow-empty
           git push origin
 
       - name: Notify Failure
         if: failure() && env.FAIL_NOTIFIED != 'true'
         run: |
-          gh pr comment ${{ github.event.issue.html_url }} -b 'Building MILLA failed, see the action run log for details: https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}'
+          gh pr comment ${{ github.event.issue.html_url }} -b 'Building Rust library failed, see the action run log for details: https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}'