Mutation for changing logged user first and last name

[fowczarek]

I want to merge this change because resolve #4289

Screenshots

Pull Request Checklist

1. Privileged views and APIs are guarded by proper permission checks.
2. All visible strings are translated with proper context.
3. All data-formatting is locale-aware (dates, numbers, and so on).
4. Database queries are optimized and the number of queries is constant.
5. Database migration files are up to date.
6. The changes are tested.
7. The code is documented (docstrings, project documentation).
8. GraphQL schema and type definitions are up to date.
9. Changes are mentioned in the changelog.

[django-queries]

Here is the report for 03d12dc (mirumee/saleor @ 4289/Change-logged-user-email-and-names)
Base comparison is c218fb0.

No differences were found. (click me)

# api.benchmark checkout
  test name                           	left count 	right count	duplicate count
  ------------------------------------	-----------	-----------	---------------
  add billing address to checkout     	         34	         34	             20
  add shipping to checkout            	          7	          7	              0
  checkout payment charge             	         14	         14	              0
  complete checkout                   	          6	          6	              0
  create checkout                     	         43	         43	             21

# api.benchmark homepage
  test name                           	left count 	right count	duplicate count
  ------------------------------------	-----------	-----------	---------------
  retrieve main menu                  	          5	          5	              0
  retrieve product list               	          4	          4	              0
  retrieve secondary menu             	          5	          5	              0
  retrieve shop                       	          2	          2	              0

# api.benchmark product
  test name                           	left count 	right count	duplicate count
  ------------------------------------	-----------	-----------	---------------
  product details                     	         13	         13	              3

# api.benchmark variant
  test name                           	left count 	right count	duplicate count
  ------------------------------------	-----------	-----------	---------------
  retrieve variant list               	          9	          9	              2

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@7a21736). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master    #4489   +/-   ##
=========================================
  Coverage          ?   90.72%           
=========================================
  Files             ?      291           
  Lines             ?    16804           
  Branches          ?     1711           
=========================================
  Hits              ?    15246           
  Misses            ?     1057           
  Partials          ?      501

Impacted Files	Coverage Δ
saleor/graphql/account/mutations.py	97.45% <100%> (ø)
saleor/graphql/account/schema.py	100% <100%> (ø)

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[codecov]

Codecov Report

Merging #4489 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #4489      +/-   ##
==========================================
+ Coverage   90.63%   90.64%   +0.01%     
==========================================
  Files         294      294              
  Lines       16942    16961      +19     
  Branches     1720     1720              
==========================================
+ Hits        15355    15374      +19     
  Misses       1082     1082              
  Partials      505      505

Impacted Files	Coverage Δ
saleor/graphql/account/mutations.py	97.45% <100%> (+0.11%)	⬆️
saleor/graphql/account/schema.py	100% <100%> (ø)	⬆️

---

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Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update c218fb0...03d12dc. Read the comment docs.