Golang 1.16: TestVerifyEC2 fails with Verify failed with error: x509: cannot verify signature: algorithm unimplemented

[eclipseo]

On Fedora Rawhide with Golang 1.16 beta 1, TestVerifyEC2 fails with:

Testing    in: /builddir/build/BUILD/pkcs7-d7302db945fa6ea264fb79d8e13e931ea514a602/_build/src
         PATH: /builddir/build/BUILD/pkcs7-d7302db945fa6ea264fb79d8e13e931ea514a602/_build/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/sbin
       GOPATH: /builddir/build/BUILD/pkcs7-d7302db945fa6ea264fb79d8e13e931ea514a602/_build:/usr/share/gocode
  GO111MODULE: off
      command: go test -buildmode pie -compiler gc -ldflags " -X github.com/fullsailor/pkcs7/version.commit=d7302db945fa6ea264fb79d8e13e931ea514a602 -X github.com/fullsailor/pkcs7/version=0 -extldflags '-Wl,-z,relro -Wl,--as-needed  -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld  '"
      testing: github.com/fullsailor/pkcs7
github.com/fullsailor/pkcs7
--- FAIL: TestVerifyEC2 (0.00s)
    pkcs7_test.go:47: Verify failed with error: x509: cannot verify signature: algorithm unimplemented
Created root cert
…

[wadey]

It looks like this is a PR open to fix this against the mozilla-services fork: mozilla-services#50