Replace unnecessary deepcopy calls with copy in tests (#752)

As per issue #648, some deepcopy calls can be replaced with copy to improve
binary trimming. This commit replaces deepcopy with copy in test files where
the objects being copied are regular Julia arrays.

- Replace deepcopy with copy for standard arrays in enzyme tests
- Replace deepcopy with copy for sparse matrices in zeroinittests

The main source files still use deepcopy for generic objects like
FunctionOperator that don't have a copy method defined.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-authored-by: Claude <[email protected]>

Author: ChrisRackauckas-Claude

test/nopre/enzyme.jl

@@ -265,9 +265,9 @@ end
 A = [1.0 2.0; 3.0 4.0]
 b = [1.0, 2.0]
 u = zero(b)
-dA = deepcopy(A)
-db = deepcopy(b)
-du = deepcopy(u)
+dA = copy(A)
+db = copy(b)
+du = copy(u)
 Enzyme.autodiff(Reverse, testls, Duplicated(A, dA), Duplicated(b, db), Duplicated(u, du))
 
 function testls(A, b, u)
@@ -281,9 +281,9 @@ end
 A = [1.0 2.0; 3.0 4.0]
 b = [1.0, 2.0]
 u = zero(b)
-dA2 = deepcopy(A)
-db2 = deepcopy(b)
-du2 = deepcopy(u)
+dA2 = copy(A)
+db2 = copy(b)
+du2 = copy(u)
 Enzyme.autodiff(Reverse, testls, Duplicated(A, dA2), Duplicated(b, db2), Duplicated(u, du2))
 
 @test dA == dA2

test/zeroinittests.jl

@@ -3,7 +3,7 @@ using LinearSolve, LinearAlgebra, SparseArrays, Test
 A = Diagonal(ones(4))
 b = rand(4)
 A = sparse(A)
-Anz = deepcopy(A)
+Anz = copy(A)
 C = copy(A)
 C[begin, end] = 1e-8
 A.nzval .= 0