better handle mixed type attributes

Author: Alexander-Barth

test/test_write.jl

@@ -1,3 +1,4 @@
+using Test
 using ZarrDatasets
 using ZarrDatasets:
     defDim,
@@ -7,13 +8,14 @@ data = rand(Int32,3,5)
 
 fname = tempname()
 mkdir(fname)
-gattrib = Dict{String,Any}("title" => "this is the title")
+gattrib = Dict("title" => "this is the title")
 ds = ZarrDataset(fname,"c",attrib = gattrib)
 
+ds.attrib["number"] = 1
 defDim(ds,"lon",3)
 defDim(ds,"lat",5)
 
-attrib = Dict{String,Any}(
+attrib = Dict(
     "units" => "m/s",
     "long_name" => "test",
 )
@@ -25,7 +27,7 @@ vtype = Int32
 
 zv = defVar(ds,varname,vtype,dimensionnames, attrib = attrib)
 zv[:,:] = data
-zv.attrib["lala"] = 12
+zv.attrib["number"] = 12
 zv.attrib["standard_name"] = "test"
 ds.attrib["history"] = "test"
 close(ds)
@@ -34,7 +36,7 @@ ds = ZarrDataset(fname)
 
 zv = ds[varname]
 
-@test zv.attrib["lala"] == 12
+@test zv.attrib["number"] == 12
 @test zv.attrib["standard_name"] == "test"
 @test ds.attrib["history"] == "test"