Always use allow_reresolve=false in downgrade workflows; remove the input

The downgrade compat workflows should never re-resolve (and thus relax)
the downgraded environment, since that defeats the purpose of testing the
oldest declared-compatible versions. Hardcode allow_reresolve: false in
both downgrade.yml and sublibrary-downgrade.yml and remove the
allow-reresolve workflow_call input so it cannot be overridden.

This removes a workflow_call input, which is breaking for any caller that
passes allow-reresolve:. Caller-cleanup PRs that drop that line must merge
before v1 is retagged.

Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com>
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: ChrisRackauckas

.github/workflows/downgrade.yml

@@ -33,11 +33,6 @@ on:
         default: "deps"
         required: false
         type: string
-      allow-reresolve:
-        description: "Allow Pkg to re-resolve (and thus relax) the downgraded environment when running tests"
-        default: false
-        required: false
-        type: boolean
       self-hosted:
         description: "Run the job on a self hosted machine"
         default: false
@@ -73,6 +68,6 @@ jobs:
       - uses: julia-actions/julia-runtest@v1
         with:
           project: "${{ inputs.project }}"
-          allow_reresolve: "${{ inputs.allow-reresolve }}"
+          allow_reresolve: false
         env:
           GROUP: "${{ inputs.group }}"

.github/workflows/sublibrary-downgrade.yml

@@ -27,11 +27,6 @@ on:
         default: ""
         required: false
         type: string
-      allow-reresolve:
-        description: "Allow the test environment to resolve transitive/test-only deps the downgrade step does not lock"
-        default: true
-        required: false
-        type: boolean
       group-env-name:
         description: "Optional env var name to set as the test group for each sublibrary (e.g. ODEDIFFEQ_TEST_GROUP)"
         default: ""
@@ -109,4 +104,4 @@ jobs:
       - uses: julia-actions/julia-runtest@v1
         with:
           project: ${{ matrix.project }}
-          allow_reresolve: ${{ inputs.allow-reresolve }}
+          allow_reresolve: false