Add CODEPAGE parameter to avoid waring; add missing NOTIFY statement; use 88-level conditional names for assignments

[vargajb]

Proposed changes

• Add missing NOTIFY statement:
  Without NOTIFY statement the user won't get notification, when the job completes execution.

• Add CODEPAGE parameter to avoid waring:
  If codepage is not given for COBOL SQL compiler, then the following warning message is issued:
  "IGYOS4078-W DSNH4791I DSNHPSRV CCSID 1140 IS USED TO PROCESS SQL, BUT DSNHDECP HAS EBCDIC CCSID 1047 IN EFFECT"

• Since we already use the 88-level conditional data names to detect the end of a loop, therefore we should use them for assignments as well.

Type of change

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• Bug fix (change which fixes one or more issues)
• New feature (change which adds functionality or features to the course)
• Translations (change which adds or modifies translations of the course)
• Documentation (change which modifies documentation related to the course)
• This change requires an update to the course's z/OS environment

Checklist:

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• I have read the Contributing Guideline
• I have included a title and description for this PR
• I have DCO-signed all of my commits that are included in this PR
• I have tested it manually and there are no regressions found
• I have commented my code, particularly in hard-to-understand areas (if appropriate)
• I have made corresponding changes to the documentation (if appropriate)

[tanto259]

Looks good to me. Thanks!