ci: upgrade script + test various ocaml versions (#331)

- add dependabot.yml
- upgrade github action versions
- test other ocaml versions
- do not check formatting anymore (ocamlformat.0.24.1 is not compatible with ocaml.5.2.0)
- update dune-project and generated opam files

.github/dependabot.yml

@@ -0,0 +1,7 @@
+version: 2
+
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: weekly

.github/workflows/main.yml

@@ -6,27 +6,27 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ocaml-compiler:
-          - 5.0.x
+        ocaml-version: [5.2.0, 5.1.1, 5.0.0, 4.14.2, 4.13.1] # does not compile with: 4.12.1, 4.11.2, 4.10.2, 4.09.1, 4.08.1
+#        ocaml-format-version: [0.24.1] # 0.24.1 is incompatible with ocaml 5.2.0
     runs-on: ubuntu-latest
     steps:
       - name: checking out dedukti repo...
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: setting up opam...
-        uses: ocaml/setup-ocaml@v2
+        uses: ocaml/setup-ocaml@v3
         with:
-          ocaml-compiler: ${{ matrix.ocaml-compiler }}
+          ocaml-compiler: ${{ matrix.ocaml-version }}
           dune-cache: true
       - name: installing dependencies...
         run: |
           opam update
           opam upgrade
           opam install . --deps-only -t
-          opam install ocamlformat.0.24.1
-      - name: Checking formatting...
-        run: |
-          eval $(opam env)
-          make fmt
+#      - name: Checking formatting...
+#        run: |
+#          eval $(opam env)
+#          opam install ocamlformat.${{ matrix.ocaml-format-version }}
+#          make fmt
       - name: Check universo compiles...
         run: |
           eval $(opam env)

dedukti.opam

@@ -9,9 +9,9 @@ homepage: "https://github.com/Deducteam/Dedukti"
 bug-reports: "https://github.com/Deducteam/Dedukti/issues"
 depends: [
   "dune" {>= "2.7"}
-  "ocaml" {>= "4.08"}
+  "ocaml" {>= "4.13.1"}
   "cmdliner" {>= "1.1.0"}
-  "tezt" {with-test & = "4.0.0"}
+  "tezt" {with-test & >= "4.0.0"}
   "menhir" {>= "20180528"}
   "odoc" {with-doc}
 ]

dune-project

@@ -12,9 +12,9 @@
 (package
     (name dedukti)
     (depends
-      (ocaml (>= 4.08))
+      (ocaml (>= 4.13.1))
       (cmdliner (>= 1.1.0))
-      (tezt (and :with-test (= 4.0.0)))
+      (tezt (and :with-test (>= 4.0.0)))
       (menhir (>= 20180528)))
     (synopsis "An implementation of The Lambda-Pi Modulo Theory")
     (description "An implementation of The Lambda-Pi Modulo Theory"))
@@ -24,7 +24,7 @@
 	(synopsis "A tool for Dedukti to play with universes")
 	(description "A tool for Dedukti to play with universes")
         (depends
-          (ocaml (>= 4.08))
+          (ocaml (>= 4.13.1))
           (dedukti (>= 2.7))
           (z3 (>= 4.8.11))
-          (tezt (and :with-test (= 4.0.0)))))
+          (tezt (and :with-test (>= 4.0.0)))))

universo.opam

@@ -9,10 +9,10 @@ homepage: "https://github.com/Deducteam/Dedukti"
 bug-reports: "https://github.com/Deducteam/Dedukti/issues"
 depends: [
   "dune" {>= "2.7"}
-  "ocaml" {>= "4.08"}
+  "ocaml" {>= "4.13.1"}
   "dedukti" {>= "2.7"}
   "z3" {>= "4.8.11"}
-  "tezt" {with-test & = "4.0.0"}
+  "tezt" {with-test & >= "4.0.0"}
   "odoc" {with-doc}
 ]
 build: [