Bump versions to prereleases for next release cycle (#1296)

This bumps the following crates to prerelease versions (not intended for
release, just to signal we're making breaking changes):

- `der`(_derive) v0.8.0-pre
- `pem-rfc7468` v1.0.0-pre
- `pkcs1` v0.8.0-pre
- `pkcs5` v0.8.0-pre
- `pkcs8` v0.11.0-pre
- `sec1` v0.8.0-pre
- `spki` v0.8.0-pre

This notably doesn't bump `x509-cert` or any crates which are dependent
upon it due to a circular dependency problem: the certificate builder
tests rely on updated public key crypto crates like `rsa`, so we'll need
to do this update in two phases: this initial set of format-only crates,
and then updating the cryptographic dependencies.

`pem-rfc7468` has been bumped to v1.0.0-pre based on the observation
that there have been no significant changes since the last release, and
that the baseline set of functionality it provides is stable.

The `minimal-versions` check is disabled for all of these crates, since
we're now using unreleased prereleases which doesn't work with these
checks.

Also bumps `sec1`'s `serdect` to use the v0.3.0-pre prerelease, and
bumpts its MSRV to 1.70 due to the `serdect` upgrade.

.github/workflows/der.yml

@@ -38,10 +38,11 @@ jobs:
       - uses: RustCrypto/actions/cargo-hack-install@master
       - run: cargo hack build --target ${{ matrix.target }} --feature-powerset --exclude-features std,arbitrary
 
-  minimal-versions:
-    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
-    with:
-        working-directory: ${{ github.workflow }}
+  # TODO(tarcieri): re-enable this when we're not using unpublished prerelease dependencies
+  #  minimal-versions:
+  #    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
+  #    with:
+  #        working-directory: ${{ github.workflow }}
 
   test:
     strategy:

.github/workflows/pkcs1.yml

@@ -41,10 +41,11 @@ jobs:
       - uses: RustCrypto/actions/cargo-hack-install@master
       - run: cargo hack build --target ${{ matrix.target }} --feature-powerset --exclude-features std
 
-  minimal-versions:
-    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
-    with:
-        working-directory: ${{ github.workflow }}
+  # TODO(tarcieri): re-enable this when we're not using unpublished prerelease dependencies
+  #  minimal-versions:
+  #    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
+  #    with:
+  #        working-directory: ${{ github.workflow }}
 
   test:
     runs-on: ubuntu-latest

.github/workflows/pkcs5.yml

@@ -40,10 +40,11 @@ jobs:
       - uses: RustCrypto/actions/cargo-hack-install@master
       - run: cargo hack build --target ${{ matrix.target }} --feature-powerset --exclude-features std
 
-  minimal-versions:
-    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
-    with:
-        working-directory: ${{ github.workflow }}
+# TODO(tarcieri): re-enable this when we're not using unpublished prerelease dependencies
+#  minimal-versions:
+#    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
+#    with:
+#        working-directory: ${{ github.workflow }}
 
   test:
     runs-on: ubuntu-latest

.github/workflows/pkcs8.yml

@@ -42,10 +42,11 @@ jobs:
       - uses: RustCrypto/actions/cargo-hack-install@master
       - run: cargo hack build --target ${{ matrix.target }} --feature-powerset --exclude-features getrandom,std,rand
 
-  minimal-versions:
-    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
-    with:
-        working-directory: ${{ github.workflow }}
+  # TODO(tarcieri): re-enable this when we're not using unpublished prerelease dependencies
+  #  minimal-versions:
+  #    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
+  #    with:
+  #        working-directory: ${{ github.workflow }}
 
   test:
     runs-on: ubuntu-latest

.github/workflows/sec1.yml

@@ -27,7 +27,7 @@ jobs:
     strategy:
       matrix:
         rust:
-          - 1.65.0 # MSRV
+          - 1.70.0 # MSRV
           - stable
         target:
           - thumbv7em-none-eabi
@@ -41,17 +41,18 @@ jobs:
       - uses: RustCrypto/actions/cargo-hack-install@master
       - run: cargo hack build --target ${{ matrix.target }} --feature-powerset --exclude-features std
 
-  minimal-versions:
-    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
-    with:
-        working-directory: ${{ github.workflow }}
+# TODO(tarcieri): re-enable this when we're not using unpublished prerelease dependencies
+#  minimal-versions:
+#    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
+#    with:
+#        working-directory: ${{ github.workflow }}
 
   test:
     runs-on: ubuntu-latest
     strategy:
       matrix:
         rust:
-          - 1.65.0 # MSRV
+          - 1.70.0 # MSRV
           - stable
     steps:
       - uses: actions/checkout@v4

.github/workflows/spki.yml

@@ -40,10 +40,11 @@ jobs:
       - uses: RustCrypto/actions/cargo-hack-install@master
       - run: cargo hack build --target ${{ matrix.target }} --feature-powerset --exclude-features arbitrary,std
 
-  minimal-versions:
-    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
-    with:
-        working-directory: ${{ github.workflow }}
+# TODO(tarcieri): re-enable this when we're not using unpublished prerelease dependencies
+#  minimal-versions:
+#    uses: RustCrypto/actions/.github/workflows/minimal-versions.yml@master
+#    with:
+#        working-directory: ${{ github.workflow }}
 
   test:
     runs-on: ubuntu-latest