Revert "Move reusable workflow to repo root"

This reverts commit a1576aeee3.

https://stackoverflow.com/questions/73026597/github-actions-suddenly-throwing-no-version-specified-for-reusable-workflows-t

"Reusable workflows" vs "local actions" use the same syntax but are
different mechanisms. :(

.github/workflows/bindgen.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: bindgen-cli
       bin: bindgen

.github/workflows/buck2.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: buck2
       git: facebookincubator/buck2

.github/workflows/cargo-bloat.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: cargo-bloat
     permissions:

.github/workflows/cargo-expand.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: cargo-expand
     permissions:

.github/workflows/cargo-fuzz.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: cargo-fuzz
     permissions:

.github/workflows/cargo-llvm-lines.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: cargo-llvm-lines
     permissions:

.github/workflows/cargo-outdated.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: cargo-outdated
     permissions:

.github/workflows/cargo-tally.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: cargo-tally
     permissions:

.github/workflows/cargo-unlock.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: cargo-unlock
     permissions:

.github/workflows/cbindgen.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: cbindgen
     permissions:

.github/workflows/cxxbridge-cmd.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: cxxbridge-cmd
       bin: cxxbridge

.github/workflows/dircnt.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: dircnt
     permissions:

.github/workflows/faketty.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: faketty
     permissions:

.github/workflows/reindeer.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: reindeer
       git: facebookincubator/reindeer

.github/workflows/rustup-toolchain-install-master.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: rustup-toolchain-install-master
       git: dtolnay-contrib/rustup-toolchain-install-master

.github/workflows/sha1dir.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: sha1dir
     permissions:

.github/workflows/star-history.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: star-history
     permissions:

.github/workflows/xargo.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    uses: ./build.yml
+    uses: ./.github/workflows/build.yml
     with:
       crate: xargo
     permissions: