refactor: get_fiscal_years API

[gavindsouza]

Changes

• Refactor get_fiscal_years API (raised for refactor!: Database frappe#16961)
• Fix import paths of PyPDF2 (ref: https://github.com/frappe/erpnext/runs/6856328546?check_suite_focus=true) (through chore(deps): Update python dependencies frappe#17127)
• Removed use of deprecated as_tuple in FrappeTestAPICase's methods (Werkzeug 2.1 ref: pallets/werkzeug@7d2784f)

[codecov]

Codecov Report

Merging #31337 (e9af68e) into develop (3a3d136) will increase coverage by 0.02%.
The diff coverage is 92.00%.

@@             Coverage Diff             @@
##           develop   #31337      +/-   ##
===========================================
+ Coverage    63.56%   63.58%   +0.02%     
===========================================
  Files          985      985              
  Lines        67567    67549      -18     
===========================================
+ Hits         42949    42954       +5     
+ Misses       24618    24595      -23     

Impacted Files	Coverage Δ
...e/period_closing_voucher/period_closing_voucher.py	88.23% <ø> (ø)
erpnext/regional/report/irs_1099/irs_1099.py	38.02% <50.00%> (ø)
erpnext/accounts/utils.py	70.09% <93.75%> (+0.28%)	⬆️
erpnext/manufacturing/doctype/job_card/job_card.py	71.09% <100.00%> (+0.06%)	⬆️
...t/accounts/report/sales_register/sales_register.py	76.02% <0.00%> (-5.85%)	⬇️
erpnext/stock/doctype/warehouse/warehouse.py	79.02% <0.00%> (-2.10%)	⬇️
...pnext/accounts/report/gross_profit/gross_profit.py	74.16% <0.00%> (-1.85%)	⬇️
...e_sales_analytics/supplier_wise_sales_analytics.py	88.52% <0.00%> (-1.64%)	⬇️
erpnext/portal/utils.py	27.69% <0.00%> (-1.54%)	⬇️
...em_wise_sales_register/item_wise_sales_register.py	61.81% <0.00%> (-1.37%)	⬇️
... and 16 more