fix #21355 remove -release flag from druntime build

[WalterBright]

https://github.com/dlang/dmd/issues/21355

[dlang-bot]

Thanks for your pull request, @WalterBright!

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Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#21356"

[WalterBright]

N.G. discussion: https://www.digitalmars.com/d/archives/digitalmars/D/OT_my_experience_with_nullable_types_C_378121.html

[rikkimax]

   core.exception.AssertError@std/experimental/allocator/building_blocks/allocator_list.d(500): Assertion failure
  ----------------
  ??:? _d_assertp [0x82758d4c0]
  ??:? nothrow @nogc bool std.experimental.allocator.building_blocks.allocator_list.AllocatorList!(std.experimental.allocator.building_blocks.allocator_list.SharedAllocatorList!(std.experimental.allocator.building_blocks.allocator_list.__unittest_L1331_C9().__lambda_L1340_C26, std.experimental.allocator.mallocator.Mallocator).Factory, std.experimental.allocator.mallocator.Mallocator).AllocatorList.deallocate(void[]) [0x826e1f275]
  ??:? shared nothrow @nogc bool std.experimental.allocator.building_blocks.allocator_list.SharedAllocatorList!(std.experimental.allocator.building_blocks.allocator_list.SharedAllocatorList!(std.experimental.allocator.building_blocks.allocator_list.__unittest_L1331_C9().__lambda_L1340_C26, std.experimental.allocator.mallocator.Mallocator).Factory, std.experimental.allocator.mallocator.Mallocator).SharedAllocatorList.deallocate(void[]) [0x826e1e545]
  ??:? nothrow @nogc void std.experimental.allocator.building_blocks.allocator_list.__unittest_L1331_C9().fun() [0x826dfffa2]

That looks suspeciously like a bug.