Rename `MModule` to `Module` and add constructor from `module` operation

[jumerckx]

This enables creating modules with attributes such as:

module attributes {transform.with_named_sequence} { ... }

[vchuravy]

Btw we could just name it Module instead of MModule.

[vchuravy]

Could you also add a test?

[codecov-commenter]

Codecov Report

Attention: 5 lines in your changes are missing coverage. Please review.

Comparison is base (3fd9f2e) 3.07% compared to head (796a6e1) 1.89%.

Files	Patch %	Lines
src/IR/IR.jl	55.55%	4 Missing :warning:
src/IR/Support.jl	0.00%	1 Missing :warning:

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Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #50 +/- ## ======================================== - Coverage 3.07% 1.89% -1.19% ======================================== Files 107 107 Lines 26060 26038 -22 ======================================== - Hits 802 493 -309 - Misses 25258 25545 +287 ```

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[jumerckx]

I renamed MModule to Module and added tests, are they thorough enough? Not sure how to get rid of: WARNING: using IR.Module in module Main conflicts with an existing identifier.

[vchuravy]

Are we doing a using LLVM?

[Pangoraw]

IIRC, I first called it MModule since otherwise it conflicted with Base.Module which is exported by Base and therefore Module was always ambiguous unless qualified.

We could do as LLVM and not export it:

julia> Base.isexported(LLVM, :Module)
false

[jumerckx]

Thanks, not exporting does the trick.

[Pangoraw]

I opened https://github.com/JuliaLang/julia/pull/53162 to allow doing:

using MLIR.IR: Module