Update MeasureTheory sections to match mathlib changes

[mjsottile]

Mathlib has changed in ways that broke compilation of a few files, required simple updates:

• Update CompleteLattice to match changes in mathlib introduced with PR [Merged by Bors] - chore: use IsLUB IsGLB in CompleteLattice leanprover-community/mathlib4#35328

• Add noncomputable to instances due to dependence on noncomputable definitions like instZeroEReal.

[mjsottile]

The following reproduces the error I saw building files directly. For example:

lake build Analysis.MeasureTheory.Section_1_4_3

Resulted in:

error: Analysis/MeasureTheory/Section_1_4_1.lean:257:4: `le_sSup` is not a field of structure `CompleteLattice`
error: Analysis/MeasureTheory/Section_1_4_1.lean:258:4: `sSup_le` is not a field of structure `CompleteLattice`
error: Analysis/MeasureTheory/Section_1_4_1.lean:259:4: `sInf_le` is not a field of structure `CompleteLattice`
error: Analysis/MeasureTheory/Section_1_4_1.lean:260:4: `le_sInf` is not a field of structure `CompleteLattice`
error: Analysis/MeasureTheory/Section_1_4_1.lean:246:2: Fields missing: `isLUB_sSup`, `isGLB_sInf`

Hint: Add missing fields:
  
  ̲ ̲ ̲ ̲ ̲i̲s̲L̲U̲B̲_̲s̲S̲u̲p̲ ̲:̲=̲ ̲_̲
  ̲ ̲ ̲ ̲ ̲i̲s̲G̲L̲B̲_̲s̲I̲n̲f̲ ̲:̲=̲ ̲_̲
error: Lean exited with code 1
Some required targets logged failures:
- Analysis.MeasureTheory.Section_1_4_1
error: build failed