[TJHeeringa]

The implemented definition IsAdjointPair required sesquilinear maps. This is a stronger requirement than necessary. This PR relaxes the conditions on IsAdjointPair to the minimal ones.

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This is needed to generalize the RKHS from InnerProductSpace/Reproducing.lean.

The location of the definition is still LinearAlgebra/SesquilinearForm/Basic. That is clearly not a good fit. However, I don't know a better location either. Places like LinearAlgebra/BilinearForm/Basic are also dealing with a less general construction.

[github-actions]

PR summary 46b43b82aa

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff (regex)

No declarations were harmed in the making of this PR! 🐙

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

## summary with just the declaration names:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh <optional_commit>

## more verbose report:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh long <optional_commit>

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

Declarations diff (Lean)

✅ Lean-aware diff — post-build, computed from the Lean environment (commit 46b43b8).

• +6 new declarations
• −0 removed declarations

+LinearMap.instSMulCommClass_1
+LinearMap.instSMulCommClass_2
+LinearMap.instSMulCommClass_3
+LinearMap.instSMulCommClass_4
+LinearMap.instSMulCommClass_5
+LinearMap.instSMulCommClass_6

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No changes to strong technical debt.
No changes to weak technical debt.

Current commit 46b43b82aa
Reference commit c20717eaa7

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/scripts/reporting/technical-debt-metrics.py pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

[mathlib-merge-conflicts]

This pull request has conflicts, please merge master and resolve them.